THEREFORE, LET US FEAR: phobethomen (1PAPS) oun: (Hebrews 4:11; 2:1-3; 12:15,25; 13:7; Proverbs 14:16; 28:14; Jeremiah 32:40; Romans 11:20; 1 Corinthians 10:12)

Click for all 12 "let us..." exhortations in Hebrews (in the NASB).

A W Pink explains the "therefore" writing that...

The exhortation begun by the apostle in Heb. 3:12 is not completed till 4:12 is reached, all that intervenes consisting of an exposition and application of the passage quoted from Ps. 95 in Heb. 3:7–11. The connecting link between what has been before us and that which we are about to consider is found in 3:19, “So we see that they could not enter in because of unbelief.” These words form the transition between the two chapters, concluding the exhortation found in vv. 12, 13, and laying a foundation for the admonition which follows...The opening words of this chapter bid us seriously take to heart the solemn warning given at the close of 3. God’s judgment upon the wicked should make us more watchful that we do not follow their steps. (Pink, A. W. An Exposition of Hebrews)

Vine introduces this chapter with the following summary...

What has been given of Israel’s history in chapter 3 is now applied with emphasis on two facts, (1) that Israel failed to enter into rest through unbelief, (2) that rest was yet assured and that believers who are not seeking rest here but who accept the present world as a wilderness, should enter God’s rest now. God has provided a means of judging unbelief and everything that would hinder a believer from entering into the rest of God and enabling him to give diligence to do so. That means is the Word of God and its power to penetrate the heart; for we all have to do with God, from whom nothing is hidden.

This portion also begins to present the main part of the great theme of the book. Here we see Christ not only in the heavens as our Great High Priest, called, qualified and perfected, possessed of the unique order of Melchizedek, but making open for us thereby the sanctuary. All this is set in connection with the new, the better covenant in contrast with the first with its ordinances. There are three subdivisions: (1) chapters 5, 6 and 7, bringing before us the priest himself, (2) chapter 8, speaking of His ministry as the Mediator of the better covenant; (3) chapters 9 and 10, showing us the way into the Holiest and how it has been opened for us. (Vine, W E: Vine's Complete Expository Dictionary of Old and New Testament Words. 1996. Nelson)

Therefore (3767) (oun) is a term of conclusion which means  consequently and thus introduces a logical result or inference from what precedes.

Therefore - Because of what he has just stated...

And to whom did He swear that they should not enter His rest, but to those who were disobedient? And so we see that they were not able to enter because of unbelief. (See note Hebrews 3:18-19) (Comment: Note that disobedience and unbelief are equated. In other words, the truth is that genuine faith obeys...therefore...!)

Because of the ''Chosen people's'' historical example and the result of their unbelief we need to have a "healthy" fear of God Who keeps His Word, both of grace and mercy and promised judgment! God is deadly serious about disobedience. Thus chapter 3 to chapter 4 is a poor chapter division. The Israelites perished because of unbelief. We today face a real peril.

Riggans writes that...

Trust and obedience are the two indispensable elements of our faith. Indeed the fundamental attitude which lies at the heart of what the Scripture calls faith is trust in God. Faith is not about knowing all the answers and being able to analyse all the doctrines without the slightest doubt or concern. It is about trusting God come what may. (Riggans, W. Focus on the Bible: Hebrews)

Let us fear (5399) (phobeo) means to frighten, terrify, be alarmed and in Classical Greek meant to cause to run away. It also conveys the sense of to revere, fear exceedingly, give reverence or be in awe of.

Barnes explains this section as...

Let us be apprehensive that we may possibly fail of that rest. The kind of fear which is recommended here is that which leads to caution and care. A man who is in danger of losing his life or health should be watchful; a seaman that is in danger of running on a lee-shore should be on his guard. So we who have the offer of heaven, and who yet are in danger of losing it, should take all possible precautions lest we fail of it (Albert Barnes. Barnes NT Commentary)

Vine writes that...

this is a definite warning concerning the spiritual rest in Christ which believers are to enjoy as God’s provision. Judaism could not procure it for Hebrews. Works cannot procure it for any believers. (Ibid)

John Piper writes that...

Reverence is the combination of admiration and fear, awe and dread, wonder and terror. It's an emotion that we were made to experience. (See John Piper's excellent discussion re the question "Do We Live in Constant Fear of Being Lost?"  Click full sermon on Hebrews 4:1-11 Be diligent to enter God's rest)

A proper fear of the Lord that should be in every Christian’s heart, like the respect of a loving child and not the dread of a frightened slave.

As A W Tozer once said...

Nothing twists and deforms the soul more than a low or unworthy conception of God

Phobeo is aorist subjunctive which in this context conveys the sense of an imperative. The idea is "Be fearful!" Note also that it is first in the verse (what is referred to as emphatic in Greek construction) because the writer does not want his readers to be complacent, unbelieving (obstinately so) and as disobedient as their forefathers.

Regarding the exhortation let us fear, John Piper makes an interesting pithy comment:

the NIV irresponsibly weakens this [let us fear] by the translation" 'Let us be careful"!

In many other places in Scripture God says "fear not" (cp Isaiah 41:10, 43:1, 5, John 14:27, 2 Ti 1:7, etc). And yet other passages concur with this passage in Hebrews and teach that there is a proper fear of the Lord that should be in every Christian’s heart, a “fear” that manifests the respect of a loving child and not the dread of a frightened slave. Proper fear motivates proper conduct as Peter emphasized writing...

And if you address as Father the One who impartially judges according to each man's work, conduct yourselves (aorist imperative = do this now! do it effectively!) in fear (phobos - noun form of verb phobeo) during the time of your stay upon earth (See note 1 Peter 1:17)

To refute, refuse or reject this clear teaching truth is to play the fool. As the wise King Solomon wrote...

Because they hated knowledge, And did not choose the fear of the LORD. (Pr 1:29).

In the context of Hebrews 3-4, the fear the writer is referring to is that they fear lest they miss heaven and especially in view of Heb 3:19 are to fear the sin of unbelief. We must fear unbelief. We should all fear not taking God at His faithful Word.

On the other hand, one should be balanced in one's fear for there is an unhealthy fear, an anxious fear or dread that abides and broods in one's soul. For discussion of Scriptures dealing with this type of undesirable fear see - How To Handle Fear

To reiterate, the writer is saying that in view of what happened to Israel (read the preceding verses in Hebrews 3, which is a poor chapter break), take this to heart and let it cause you to tremble. This is serious. Have you heard and heard and heard what God has said but you've never really heeded, never embraced Christ, never entered into His rest. Then you are in Hebrews 4:1. Peter said we need to make sure of our calling and election writing...

Therefore, brethren, be all the more diligent to make certain about His calling and choosing you; for as long as you practice these things, you will never stumble; for in this way the entrance into the eternal kingdom of our Lord and Savior Jesus Christ will be abundantly supplied to you. (See notes 2 Peter 1:10; 1:11).

If you've missed the promise, then come on in. The promise remains.

Do not fear those who kill the body, but are unable to kill the soul; but rather fear Him who is able to destroy both soul and body in hell (Mt 10:28).

IF, WHILE A PROMISE REMAINS OF ENTERING HIS REST: mepote kataleipomenes (PPPFSG) epaggelias eiselthein (AAN) eis ten katapausin autou:  (9; Numbers 14:34; 1 Samuel 2:30; Romans 3:3,4; 2 Timothy 2:13)

See excursus on Rest in Hebrews 4.

While (mepote) Lest at any time. The kind of "fear" which is recommended here is what leads to caution and care. A man who is in danger of losing his life or health should be watchful; a seaman that is in danger of running on shore should be on his guard. So we who have the offer of heaven, and who yet are in danger of losing it, should take all possible precautions lest we fail of it.

Promise (1860) (epaggelia from epí = intensifies verbal meaning + aggéllo = to tell, declare) originally referred to an announcement or declaration (especially of a favorable message) but in later Greek came to mean a declaration to do something with the implication of obligation to carry out what is stated (thus a promise or pledge). Epaggelia was primarily a legal term denoting summons, a promise to do or give something, but in the NT speaks primarily of the promises of God.

Epaggelia is used in Hebrews 14 times in 13 verses (27.4% of all 51 NT uses) (See notes Hebrews 4:1, Hebrews 6:12, 6:15, 6:17, Hebrews 7:6, Hebrews 8:6, Hebrews 9:15, Hebrews 10:36, Hebrews 11:9, 11:13, 11:17, 11:33, 11:39)

TDNT summarizes this word group writing that it has the following nuances...

a. The first sense is “to indicate,” “declare,” “declaration,” “report.” b. When the state declares something, it becomes an “order.” c. In law we find the senses “accusation” and “delivery of a judgment.” d. We then find the senses “to declare an achievement,” “to show one's mastery,” “to profess a subject.” e. Another sense is “to offer,” “to promise,” “to vow.” As regards promises, tension between word and deed is felt, so that promises are often seen as worthless. f. A special type of promise is the “promise of money,” and in this sense the idea of a “subscription” or “donation” arises (state liturgies, gifts to rulers at their accession, priests promising gifts in support of their candidature). g. In the Hellenistic period we also find a sacral use for the “proclamation” of a festival. Among all the instances, only one example has been found for the promise of a deity. (Kittel, G., Friedrich, G., & Bromiley, G. W.  Theological Dictionary of the New Testament. Eerdmans)

There is an interesting play on words...the OT example speaks of the Promised Land, whereas the writer in Hebrews speaks of something far greater than land. He speaks of our spiritual rest in Christ.

Remains (2641) (kataleipo from kata = intensifies meaning + leipo = leave behind) conveys in a strong way the sense of to leave, abandon or forsake. In the passive sense as used here in Hebrews 4:1 kataleipo means to remain behind for a purpose.

Kataleipo is also used in...

Hebrews 4:6 (note) Since therefore it remains for some to enter it, and those who formerly had good news preached to them failed to enter because of disobedience,

Hebrews 4:9 (note) There remains therefore a Sabbath rest for the people of God.

Kataleipo is in the present tense passive meaning "continually caused to remain" or "a promise still being left". That is, it was given to believers among Israel of old, and holds good still for all.

The passive voice indicates an outside force effects the action of keeping the door of the Ark open, so to speak. When God decides the time is up, it is up! (see note Hebrews 9:28) Even for those "almost persuaded" such were Agrippa (Acts 26:28), the young ruler Mark 10:21, and all those who are "almost" but not "quite" prepared to give up the world and to surrender themselves to the Redeemer.

To all these the promise of rest remains, if they will accept of salvation as it is offered in the gospel; all of them cherish a hope that they will be saved; and all of them are destined alike to be disappointed. With what earnestness, therefore, should we strive that we may not fall short of or away from the amazing grace of God!

Of entering (1525) (eiserchomai) means to go or come into or to enter into.

Compare Elijah's query...

1Ki 18:21 How long will you hesitate between two opinions? If the LORD is God, follow Him; but if Baal, follow him." But the people did not answer him a word.

Rest (2663) (katapausis from katá = intensifies or "down" conveying sense of  permanency + paúo = make to cease) (Click here  for more detailed word study of katapausis) describes literally a ceasing from one's work or activity. Thayer cites a use in the active sense of a putting to rest as used in the sentence "a calming of the winds". Metaphorically as used in the present verse, katapausis speaks of the spiritual fulfillment God provides for His people.

This is not just any rest, but the Creator's rest! The wilderness wanderings represent those who had heard the truth but who would not believe that truth with the result that they spend their whole life in restless unbelief. For believers, God’s rest includes His peace, confidence of salvation, reliance on His strength, and assurance of a future heavenly home

Regarding the rest of God Barnes writes that this rest is...

the rest of the world where He dwells. It is called His rest, because it is that which He enjoys, and which He alone can confer. There can be no doubt that Paul refers here to heaven, and means to say that there is a promise left to Christians of being admitted to the enjoyment of that blessed world where God dwells. (Albert Barnes. Barnes NT Commentary)

Roy Zuck in "A Biblical Theology of the NT" (Dallas Theological Seminary) has a note that “promised rest” in Hebrews and interprets it as earthly, millennial blessings as well as the believer’s eternal future in heaven.

Katapausis is used 8 times in the NT, all but one in the epistle to the Hebrews...

Acts 7:49 'Heaven is My throne, And earth is the footstool of My feet; What kind of house will you build for Me?' says the Lord; 'Or what place is there for My repose?

Hebrews 3:11 As I swore in My wrath, 'They shall not enter My rest.'

Hebrews 3:18 And to whom did He swear that they should not enter His rest, but to those who were disobedient?

Hebrews 4:1 Therefore, let us fear lest, while a promise remains of entering His rest, any one of you should seem to have come short of it.

Hebrews 4:3 For we who have believed enter that rest, just as He has said, "As I swore in My wrath, They shall not enter My rest," although His works were finished from the foundation of the world.

Hebrews 4:5 and again in this passage, "They shall not enter My rest."

Hebrews 4:10 For the one who has entered His rest has himself also rested from his works, as God did from His.

Hebrews 4:11 Let us therefore be diligent to enter that rest, lest anyone fall through following the same example of disobedience.

Barclay has the following analysis of katapausis noting that...

In a complicated passage like this it is better to try to grasp the broad lines of the thought before we look at any of the details. The writer is really using the word rest (katapausis) in three different senses. (i) He is using it as we would use the peace of God. It is the greatest thing in the world to enter into the peace of God. (ii) He is using it, as he used it in Hebrews 3:12, to mean The Promised Land. To the children of Israel who had wandered so long in the desert the Promised Land was indeed the rest of God. (iii) He is using it of the rest of God after the sixth day of creation, when all God’s work was completed. This way of using a word in two or three different ways, of teasing at it until the last drop of meaning was extracted from it, was typical of cultured, academic thought in the days when the writer to the Hebrews wrote his letter. (Barclay, W: The Daily Study Bible Series, Rev. ed. Philadelphia: The Westminster Press or Logos)

Illustration - Few have lived as stressful and frenetic a life as Hudson Taylor, founder of China Inland Mission. Day and night this was his secret, “just to roll the burden on the Lord.” Frequently those who were wakeful in the little house at Chinkiang might hear, at two or three in the morning, the soft refrain of Mr. Taylor’s favorite hymn [“Jesus, I am resting, resting in the joy of what Thou art”]. He had learned that for him, only one life was possible—just that blessed life of resting and rejoicing in the Lord under all circumstances, while He dealt with the difficulties, inward and outward, great and small.

ANY ONE OF YOU MAY SEEM TO HAVE COME SHORT OF IT: doke (3SPAS) tis ex humon husterekenai (RAN): (Matthew 7:21-23,26,27; 24:48-51; 25:1-3; Luke 12:45,46; 13:25-30; Romans 3:23; 1 Corinthians 9:26,27)

Ray Stedman explains this passage writing that...

In Hebrews 4:1 we are given the first hint that the promise of rest given to Israel envisaged more than entering the Promised Land. It is, he says, a promise which still stands, that is, was not satisfied by entering Canaan, but still exists at the time of his writing. Furthermore, his readers stand in danger of missing it unless they are careful. The Greek construction of the phrase that none of you be found to have fallen short of it indicates that wrong behavior, such as disobedience or long-continued grumbling, suggests the heart is unchanged and unbelieving. Be found refers to God’s knowledge of the heart and his actions based on that knowledge. (Hebrews 4:1-2 A Promise Requires a Response)

In Matthew Jesus gave a stern warning that parallels the warning by the writer of Hebrews...

Not everyone who says to Me, 'Lord, Lord,' will enter the kingdom of heaven; but he who does the will of My Father who is in heaven. Many will say to Me on that day, 'Lord, Lord, did we not prophesy in Your name, and in Your name cast out demons, and in Your name perform many miracles?' And then I will declare to them, 'I never knew you; DEPART FROM ME, YOU WHO PRACTICE LAWLESSNESS. (See note Matthew 7:21; 7:22; 7:23)

Any one of you (5100) (tis) means one, someone or a certain one. This pronoun tis is used particularly and generally of some person or thing whom one cannot or does not wish to name or specify particularly.

Though two spies brought back a good report, 600,000 men rejected it.

May seem (1380) (dokeo) means to hold an opinion based upon appearances which may be significantly different from reality. It means to regard something as presumably true, without particular certainty.

Seem is a way of softening the warning so that the writer refrains from saying that any of them actually missed or will miss the promise.

To come short (5302) (hustereo from hústeros = last, latter, terminal, hindmost)  has the basic meaning of come to late (in time) or to come after (in terms of space) and thus it means to fail in something, come short of, miss, not to reach. Hustereo has the basic meaning of being last or inferior. It means to be left behind in the race and so fail to reach the goal, to fall short of the end, to lack. It means to come late or too tardily.

It means to be excluded (see note Hebrews 12:15) or as in Hebrews 4:1 as coming too late through one's own fault miss and so to fail to reach the intended objective or goal.

In several of the NT passages hustereo means to be in short supply, to fail,  to give out or to lack. Hustereo can mean to experience deficiency in something advantageous or desirable and thus to be lacking, go without or come short of (as in Mt 19:20).

Hustereo is used 14 times in the Lxx (Num. 9:7, 13; Neh. 9:21; Job 36:17; Ps. 23:1; 39:4; Eccl. 6:2; 9:8; 10:3; Cant. 7:2; Dan. 4:33; 5:27; Hab. 2:3) and 16 times in the NT (see below) (Matt. 19:20; Mk. 10:21; Lk. 15:14; 22:35; Jn. 2:3; Rom. 3:23; 1 Co. 1:7; 8:8; 12:24; 2 Co. 11:5, 9; 12:11; Phil. 4:12; Heb. 4:1; 11:37; 12:15)

Hustereo is used in the famous "Hall of Faith" chapter, Hebrews 11...

They were stoned, they were sawn in two, they were tempted, they were put to death with the sword; they went about in sheepskins, in goatskins, being destitute (hustereo), afflicted, ill-treated (see note Hebrews 11:37)

The meaning of hustereo is further illustrated in the following verses...

(At the wedding in Cana site of Jesus' first recorded miracle) And when the wine gave out, (hustereo) the mother of Jesus said to Him, "They have no wine." (John 2:3)

Now when he (the prodigal son) had spent everything, a severe famine occurred in that country, and he began to be in need (hustereo). (Luke 15:14)

The young man said to Him, "All these things I have kept; what am I still lacking (hustereo)?" (Mt 19:20)

If our perseverance should “fall short” like the wine at the wedding feast in Cana, the party could be ruined (John 2:3). If our faith runs out like the prodigal son’s money, we may find ourselves very impoverished (Lu 15:14). It is easy for this deficiency to come on us unnoticed, like the rich young ruler’s lack of freedom from his wealth (Mt 19:20).

The perfect tense means they came short at a point in time and are still short - it speaks of the permanence of their condition!  The entire phrase in Hebrews 4:1 could be translated

lest you think you have come too late to enter into the rest of God

This same verb hustereo is used later in Hebrews, the writer warning... 

See to it that no one comes short (hustereo) of the grace of God; that no root of bitterness springing up causes trouble, and by it many be defiled  (see note Hebrews 12:15)

With reverential fear all are to examine their own spiritual condition (cf. 1Cor 10:12; 2Cor 13:5) and to actively press for commitment on the part of others (cf. Jude 1:23).

Hustereo means to essentially to be found to come short as in Romans 3 where Paul writes that ...

all have sinned and fall short (hustereo) of the glory of God (see note Romans 3:23)

When you come short of something, you can miss it an inch or a mile, but you still miss it!  So those in Romans 3:23 have missed it a "mile". There are others who have missed it by only an "inch". For example, take the man that Mark wrote about...

And looking at him (a man who ran up to Jesus and knelt before Him), Jesus felt a love for him, and said to him, "One thing you lack (hustereo): go and sell all you possess, and give to the poor, and you shall have treasure in heaven; and come, follow Me." But at these words his face fell, and he went away grieved, for he was one who owned much property. And Jesus, looking around, said to His disciples, "How hard it will be for those who are wealthy to enter the kingdom of God!  (Mark 10:21-23)

In this declaration by Jesus the verb lack is the same word hustereo (come short) used here in Hebrews 4. Jesus was telling the man (and all who have ears to hear) that "you are coming short in just one thing".

Isn't it amazing how some can come so close! They are in a good Bible believing church, they know stories and verses in the Bible, they know the message of good news, they are "good" people, etc, etc...but they lack one thing…they've never confessed Jesus as Lord and Savior of their life the importance of which Paul explains...

But what does it say? "THE WORD IS NEAR YOU, IN YOUR MOUTH AND IN YOUR HEART"-- that is, the word of faith which we are preaching, 9 that if you confess with your mouth Jesus as Lord, and believe in your heart that God raised Him from the dead, you shall be saved; 10 for with the heart man believes, resulting in righteousness, and with the mouth he confesses, resulting in salvation. 11 For the Scripture says, "WHOEVER BELIEVES IN HIM WILL NOT BE DISAPPOINTED (means to be caused to be much ashamed, humiliated or disgraced!)." (See notes Romans 10:8; 10:9; 10:10; 10:11)

When you come so close yet are still short, you might even presume that you have entered into the rest (like a "vaccination" or being inoculated with the inactive virus to prevent you from getting the real viral disease), and so this is why it is so important to continue to encourage one another daily while there is still time. Coming to Bible study means nothing if Christ is not in your heart. You can know a lot in your head but the real issue is to make certain of your calling and election. Many will say to Jesus in that day "Lord, Lord" but He will say "I never knew you." (See notes Matthew 7:21; 7:22; 7:23)

Among those WHO COME SHORT OF GOD'S REST will be the following classes:

(1) Those who are professors but who have never known anything of true piety.

(2) those who are expecting to be saved by their own works.

(3) those who defer attention to the subject from time to time until it becomes too late. They expect to reach heaven, but they are not ready to give their hearts to God "now," and the subject is deferred from one period to another, until death arrests them unprepared.

(4) those who have been awakened to see their guilt and danger, and who have been almost but not quite ready to give up their hearts to God.

Such were Agrippa (Acts 26:28), the young ruler Mk 10:21, and such are all those who are "almost" but not "quite" prepared to give up the world and to devote themselves to the Redeemer.

To all these the promise of rest is made, if they will accept of salvation as it is offered in the gospel; all of them cherish a hope that they will be saved; and all of them are destined alike to be disappointed. With what earnestness, therefore, should we strive that we may not fail of the grace of God!

Here are all the uses of hustereo (words in bold below represent translation of hustereo) in the NT...

Matthew 19:20 The young man said to Him, "All these things I have kept; what am I still lacking?"

Mark 10:21 And looking at him, Jesus felt a love for him, and said to him, "One thing you lack: go and sell all you possess, and give to the poor, and you shall have treasure in heaven; and come, follow Me."

Luke 15:14 "Now when he had spent everything, a severe famine occurred in that country, and he began to be in need.

Luke 22:35 And He said to them, "When I sent you out without purse and bag and sandals, you did not lack anything, did you?" And they said, "No, nothing."

John 2:3 And when the wine gave out, the mother of Jesus said to Him, "They have no wine."

Romans 3:23  for all have sinned and fall short of the glory of God,

1 Corinthians 1:7 so that you are not lacking in any gift, awaiting eagerly the revelation of our Lord Jesus Christ,

1 Corinthians 8:8 But food will not commend us to God; we are neither the worse if we do not eat, nor the better if we do eat.

1 Corinthians 12:24 whereas our seemly members have no need of it. But God has so composed the body, giving more abundant honor to that member which lacked,

2 Corinthians 11:5 For I consider myself not in the least inferior to the most eminent apostles.

2 Corinthians 11:9 and when I was present with you and was in need, I was not a burden to anyone; for when the brethren came from Macedonia, they fully supplied my need (related word husterema), and in everything I kept myself from being a burden to you, and will continue to do so.

2 Corinthians 12:11 I have become foolish; you yourselves compelled me. Actually I should have been commended by you, for in no respect was I inferior to the most eminent apostles, even though I am a nobody.

Philippians 4:12