Spurgeon asks...

What Christian ever wishes to be barren or unfruitful? Is it not the aspiration of every branch in the true vine to bring forth much fruit?

For (1063) (gar) is a marker showing the cause or reason for something.

For is at the beginning of each of these verses and introduces a positive and a negative incentive to grow spiritually. Note that NASB adds "if" to the translation which suggests that some might not have the qualities mentioned in (see notes 2 Peter 1:5; 1:6; 1:7) but in fact that is not at all what the word "are" (see below) indicates as this verb clearly indicates that there is no doubt about the the reader's possession of these qualities at least in some measure.

"These" refers to the possession and progress in the Christian virtues just delineated. What would you say about a person who evidences none of these qualities?

John Calvin adds that

"you will at length prove that Christ is really known by you, if ye be endued with virtue, temperance, and the other endowments. For the knowledge of Christ is an efficacious thing and a living root, which brings forth fruit."

Are (huparcho from hupo - under + archê - a beginning) means to be, to be in existence, involving an existence or condition both previous to the circumstances mentioned and continuing after it. Huparcho emphasizes that these spiritual qualities (see notes 2 Peter 1:5; 1:6; 1:7) “belong to” all Christians at least to some degree and are "at their disposal" so to speak. The phrase  "are yours" (humin huparchonta) is a strong expression denoting that which actually exists as one's possession.

Huparcho for example was used of a property, indicating one owned it and could dispose of it as he desired (cf of Barnabas' tract of land Acts 4:37).

The NIV picks us this truth better than most of the other translations using the word "possess" (present participle would more literally be "continually possessing" ~ their continual possession whether you feel like it or not). Phillip's paraphrase also conveys this truth --"If you have these qualities existing...".

These wonderful characteristics of the "divine nature" (see notes 2 Peter 1:5; 1:6; 1:7) have become a rightful part of the new creation you are in Christ, not a mere fleeting manifestation. Maybe you don't feel very "godly" as you read these words and the enemy is bombarding your mind (that's where the real "spiritual war" is waged in every saint and that battle is over truth versus lies, falsehood and error) with "fiery missiles" saying things like "Who do you think you are? You're not acting very godly". You need to take those thoughts captive (2Cor 10:5) and instead let your mind dwell on the truth about you (see note on Philippians 4:8) - you dearly beloved are a possessor of "godliness".

Now live out the truth you know, for as a man or woman thinks within themselves so they are (Pr 23:7).

To reiterate, since you have become partakers of the divine nature, all of the qualities (see notes 2 Peter 1:5; 1:6; 1:7) and more reside in you right now no matter how you "feel" (remember "feelings" can often be deceiving). The truth about you is that the resurrected Christ now lives in you in the form of the Holy Spirit (see note on Colossians 1:27).

Peter is exhorting every saint to choose now to allow Him to express Himself through you. And it is a voluntary choice we must each make and make each day...many times during the day. God won't force us to deny ourselves and to set our mind on the things of the Spirit rather than the things of the flesh. We each must do that. But oh the rewards for letting the Spirit fill us and control us (Eph 5:18, Gal 5:16). The more we choose as His bondservants to allow Jesus to be the Lord and Master of every area of our life (see notes on Romans 12:1, 12:2) the more these qualities will increase and superabound, bearing much fruit, fruit that remains for eternity. Why are we so stubborn, hard headed, rebellious and resistant to the Word and the Spirit when all God wants to do is pour forth blessing upon our life?!

Wuest adds that huparcho 

"refers to an antecedent condition protracted into the present. It speaks of possession." (Wuest goes on to quote Marvin Vincent)

“In the sense of 'being' the verb is stronger than the simple einai ‘to be’; denoting 'being' which is from the beginning, and therefore attaching to a person as a proper characteristic, something belonging to him, and so running into the idea of rightful possession as above.”

Thus, the possession of the Christian virtues by the believer is a natural, expected thing by reason of the fact that he has become a partaker of the divine nature. And they are not a spasmodic possession either, present one day and absent the next. Indeed, if they were not present in the life, one could well discount the person’s claim of being a child of God." (Wuest, K. S. Wuest's Word Studies from the Greek New Testament: Eerdmans)

If these qualities are not 'yours'' then one must be circumspect and consider Paul's serious warning to...

"Test (present imperative) yourselves to see if you are in the faith; examine yourselves! Or do you not recognize this about yourselves, that Jesus Christ is in you--unless indeed you fail the test? (2Co13:5)

In this preceding verse ''yourselves'' is emphatic! How does one assess whether he "fails the test"? There is no power of Christ in their life over sin, no progressive sanctification, none of the virtues listed above, no spiritual fruit, etc.

Why should we study these qualities in detail? If we don't know what they mean how can we even discern whether they are present and increasing? Also if these character traits reflect the "real thing" (genuine Christianity being lived out), then we must know them in order to be able to detect the counterfeit described in the next chapter.

AND ARE INCREASING: kai pleonazonta (PAPNPN): (1 Cor 15:58; 2 Cor 8:2; 2 Co 8:7 Php 1:9; Col 2:7; 3:16; 1Th 3:12; 4:1; 2 Th 1:3)

Increasing (4121) (pleonazo from pleion = more)  means to bring forth in abundance, to become more and more so as to be in abundance and finally to even superabound. The present tense pictures them as ideally continually increasing. Don't read over this section too quickly without asking yourself, "Are these qualities truly increasing in my life or am I in a spiritual rut?" Dearly beloved, life is too short and eternity too long to not be soberly circumspect and "brutally" honest with ourselves!

J. Vernon McGee quips

"Here he starts multiplying again. Peter is great with mathematics." (McGee, J V: Thru the Bible Commentary:  Thomas Nelson)

Peter desires that the qualities (see notes 2 Peter 1:5; 1:6; 1:7) (these things) ought not to be static but to be continually increasing in every believer’s life. Some believers may feel good that these qualities are seen in themselves from time to time. But Peter says they should continually (pleonazo is in the present tense = continuous action) superabound in us.  There are degrees of ownership of these qualities, implying degrees of productivity in one’s intimacy with Christ. To keep growing in these qualities, one must practice them in the real life classroom of life.  Lack of spiritual growth in these areas is a sign of spiritual deterioration. We need to apply all diligence for this is a serious issue for our spiritual health.

MacArthur explains that...

"increasing" as meaning ""to have more than is necessary" or "to bring forth in abundance." There ought to be enough fruit in your life to prove beyond a shadow of a doubt whom you belong to. God is not interested in a marginal manifestation. Some Christians will manifest some productivity, then manifest nothing. However, there should be more fruit in a believer's life than necessary to prove he is a believer. Many unbelievers have difficulty understanding Christianity because so many Christians manifest no fruit. Many people claim to be Christians, but there's nothing in their life to support their claim."

In (Jn 15:5) Jesus taught that a disciple should bring forth ''much fruit" (see discussion below on "What is fruit according to the Word of God?) for as we bring in a bountiful crop, we bring glory to our heavenly Father and also prove ourselves to be His disciples (see note Matthew 5:16, Jn 15:8). If you are becoming more and more like Jesus Christ (Christ is increasing & you are decreasing Jn 3:30) you have the kind of character and conduct that God can trust with blessing and are fruitful because you are faithful. Although these character qualities exist in a seed state in every believer (we're all complete in Christ and are possessors of His divine nature), one must continually cultivate them (pull out the weeds of defilement 2Cor 7:1,Ja 1:27, water with the Word Eph 5:26, etc) so that they increase and produce fruit that remains (Jn 15:16)

Wuest comments on saints "increasing" in the fruit of the virtues just mentioned...

"The Spirit-filled life is the overflowing life. It is like an artesian well (click Artesian Well diagram to help visualize this great illustration of the "Spirit controlled Christ life") whose source is higher than its outflow, the outflow being spontaneous by reason of that fact. The source of the Christian life is God; the outflow, through the believer. But the Christian life that does not run over, or overflow with spiritual blessings to others, is never a source of spiritual refreshment to others. A farmer once said to his helper who always filled the buckets of grain only three fourths full when they should have been full, “the buckets are never full until they are running over.” So a Christian is never filled with the Spirit and spiritual blessings until his life is running over with the good things of God, refreshing the lives of others."

THEY RENDER YOU: ouk argous oude akarpous kathistesin (3SPAI): When the qualities are increasing the "make you not idle nor unfruitful". 

Render (2525) (kathistemi from katá = down + histemi = to stand) (Click word study on kathistemi) means literally “to stand or set down".  Most NT uses refer to "setting someone in office" or appointing or assigning a person to a position of authority, to put in charge, to appoint one to administer an office or  to constitute.

A saint's superabounding possession of the qualities in constitutes them as "neither useless nor unfruitful". The tense is present which indicates an ongoing rendering.

As you read this note the truth is that if you are a believer, you are either in one of two states -- advancing or regressing on the highway of holiness -- "Onward ho!" should be the believer's byword. No standing still. And oh to yearn for the fruit borne by running the course with endurance and pressing on toward the goal for the prize of the upward call. The one who runs the race, fights the fight and keeps the faith is the one who realizes strength in their spirit and security in their salvation. Failure to persevere in the development of this Christian character leads to barrenness, unfruitfulness, blindness, shortsightedness, and forgetfulness. So let your light shine and press on so that you are not trampled on like "tasteless salt" thrown out under the feet of men. (Mt5:13-16)

NEITHER USELESS: ouk argous: (Pr 19:15; Mt 20:3,6; 25:26; Ro 12:11; 1Ti 5:13; Heb 6:12)

Neither (3756) is ouk conveying absolute negation in the Greek. This negative combined with the two adjectives that follow gives the force of a strong positive assertion.

Useless (692) (argos from a = without + érgon = work) literally means without work, without labor, doing nothing, as one not working the ground and so living without labor. As employed in the New Testament, argos always describes something inoperative or unserviceable. Argos describes that which is not working, ineffective, barren, yielding no return or worthless, not accomplishing anything. 

Argos was used to describe money that was yielding no interest or of a field lying fallow.

Argos conveys several ideas depending on the context - (1) unemployed - without anything to do (Mt 20:3,6, 1Ti 5:13); (2)  being unwilling to work, wanting nothing to do, shunning the labor which one ought to perform - idle, neglectful or lazy (as used in Titus 1:12) and (3) unproductive - useless, unprofitable or worthless (Ja 2:20, 2 Peter 1:8; Mt 12:36).

Argos is used 7 times in the NT (see uses below) and is translated in the NASB as: careless, 1; idle, 4; lazy, 1; useless, 2. KJV translates it as: barren, 1; idle, 6; slow, 1. Argos is found once in the Septuagint (LXX) (1 Ki 6:7)

Matthew 12:36 "And I say to you, that every careless (literally "not working", barren, unproductive) word that men shall speak, they shall render account for it in the day of judgment. (Comment: Re-read this verse and think about the implications of what comes out of our mouths. Are our words "working" - ergon - words, words that are productive and which edify? "Not working" words include those that are flippant, irresponsible, hypocritical or in any way inappropriate. cf Eph 4:29)

Matthew 20:3 "And he went out about the third hour and saw others standing idle in the market place;

Matthew 20:6 "And about the eleventh hour he went out, and found others standing; and he said to them, 'Why have you been standing here idle all day long?'

1 Timothy 5:13 And at the same time they (younger widows) also learn to be idle, as they go around from house to house; and not merely idle, but also gossips and busybodies, talking about things not proper to mention.

James 2:20 (see below also) But are you willing to recognize, you foolish fellow, that faith without works is useless (unprofitable, worthless - carries the idea of fruitlessness - see parallel thought in note on Matthew 7:19)? (Comment: What does a fruitless life demonstrate?)

Titus 1:12 One of themselves, a prophet of their own, said, "Cretans are always liars, evil beasts, lazy gluttons." (see note)
 

Argos can pertain to being without anything to do, unemployed or idle. In this sense it does not necessarily connote laziness but merely points up the fact that they were unemployed at the time. For example in Jesus' parable of the vineyard He related how the landowner went to hire laborers "And he went out about the third hour and saw others standing idle in the market place." (Mt 20:3).
 

Argos is not a picture of one who is unavoidably unemployed but of one who avoids labor for which he or she should assume responsibility ("we are His workmanship" Eph 2:10).

James (Js 2:20) uses argos to describe a faith that fails to show itself in works. Jesus warned that

“Every tree that does not bear good fruit, is cut down and thrown into the fire” (see note Matthew 7:19).

A fruitless life is proof that one does not belong to God and is unacceptable to God, because this life does not have His divine life within. Faith apart from works is head belief, and therefore dead belief.

Argos is like money gaining no interest and fertile land yielding no crops.

Argos describes that which does not fulfill its purpose. In a spiritual sense argos means "to produce no good for God." With the virtues mentioned above increasing in one’s life (see notes 2 Peter 1:5; 1:6; 1:7), a Christian will not be useless or effective.

Peter's point is that in contrast to being barren, inactive, indolent, and useless, if these virtues are increasing in one’s life, this Christian's life will not be useless or ineffective.

Paul in a parallel passage writes

"So then, while we have opportunity (see in depth study of this word kairos), let us do good (not only being useful or profitable to them, but also doing what is for their spiritual good and advantage; see study of good deeds) to all men, and especially to those who are of the household of the faith (the first test of our love for God is our love for His other children, our brothers and sisters in Christ)." (Gal 6:10)

MacArthur gives an example to illustrate "useless"

"People have said to me, "I have a friend who received Christ and came to church and Bible study for awhile. But now he never comes. He just doesn't seem interested. I can't figure out if he's a Christian or not." I have had the same problem. There was a man who used to come to Grace Church and teach in the children's department. But he has not darkened our door for many years. People have asked me if he's a believer. To be perfectly honest, I haven't the faintest idea because he is indistinguishable from an unbeliever. He is argos-- dead and barren."

We probably all know someone like this. How eternally tragic to be a believer blessed with every spiritual blessing in the heavenly places in Christ, possessing every accoutrement necessary for life and godliness, including access to all of God's precious and magnificent promises, and most significantly to be a sharer in God's divine nature...and yet despite all these spiritual advantages, to still be utterly useless to God, spiritually bankrupt so to speak! Can you imagine what that day will be like for these saints when they

"appear before the judgment seat of Christ, so that each one may be recompensed for his deeds in the body, according to what he has done, whether good or bad" (2Cor 5:10)

and  

"each man's work will become evident; for the day will show it because it is to be revealed with fire, and the fire itself will test the quality of each man's work. If any man's work which he has built on it remains, he will receive a reward. If any man's work is burned up, he will suffer loss; but he himself will be saved, yet so as through fire." (1Cor 3:13-15)

MacDonald adds these thoughts on the "useless" life:

"Only the life lived in fellowship with God can be truly effective. The guidance of the Holy Spirit eliminates barren activity and insures maximum efficiency. Otherwise, we are shadow-boxing, or sewing without thread."

In this section, it is clear that Peter's desire is that believers "grow in the grace and knowledge of our Lord and Savior Jesus Christ" (see note 2 Peter 3:18) as expressed in this little poem by Eliza Hewitt

NOR UNFRUITFUL: oude akarpous kathistesin (3SPAI):  (Mt 13:22; Jn 15:2;Jn 15:6; Titus 3:14)

Unfruitful (175) (akarpos from a = without + karpos = fruit, produce) means barren, without fruit or unprofitable. Akarpos pictures a tree without fruit under the most favorable of circumstances.

Akarpos is used 7 times in the NT in the NASB (Mt;