FOR BY ONE OFFERING HE HAS PERFECTED FOR ALL TIME: mia gar prosphora teteleioken (3SRAI) eis to dienekes: (1; 7:19,25; 9:10,14)

Perfected (5048) (teleioo related to teleios from telos = an end, a purpose, an aim, a goal, consummate soundness, idea of being whole) means to accomplish or bring to an end or to the intended goal (telos). It means to be complete, mature, fully developed, full grown, brought to its end, finished, wanting nothing necessary to completeness or in good working order. It does not mean simply to terminate something but to carry it out to the full finish which is picked up in the translation "perfected". Teleioo signifies the attainment of consummate soundness and includes the idea of being made whole. Interestingly the Gnostics used teleios of one fully initiated into their mysteries and that may have been why Paul used teleios in this epistle.

The perfect tense here in Hebrews 10:14 speaks of the permanence of this perfection and thus refers to past tense salvation or positional sanctification. Believers are forever perfect in Christ which is how God now see them.

In Hebrews 12:2 (see note) Jesus is designated as "the author and perfecter of faith" where perfecter is teleiotes, the Completer, the One Who reached the goal so as to win the prize so to speak.

Wuest has this note on the NT word group (telos, teleioo, teleios, teleiosis, teleiotes)...

Teleios the adjective, and teleioo the verb. The adjective is used in the papyri, of heirs being of age, of women who have attained maturity, of full-grown cocks, of acacia trees in good condition, of a complete lampstand, of something in good working order or condition. To summarize; the meaning of the adjective includes the ideas of full-growth, maturity, workability, soundness, and completeness. The verb refers to the act of bringing the person or thing to any one of the aforementioned conditions. When applied to a Christian, the word refers to one that is spiritually mature, complete, well-rounded in his Christian character.

Richards commenting on the word group (telos, teleioo, teleios, teleiosis, teleiotes) writes that

These words emphasize wholeness and completeness. In the biological sense they mean "mature," or "full grown": the person, animal, or plant achieved the potential inherent in its nature. The perfect is the thing or person that is complete, in which nothing that belongs to its essence has been left out. It is perfect because every potential it possesses has been realized. (Richards, L O: Expository Dictionary of Bible Words: Regency)

Telioo is used 19 times of 24 total NT uses in Hebrews, often in the sense of to make perfect or fully cleanse from sin in contrast to ceremonial (Levitical) cleansing. The writer is emphasizing the importance of perfection... (which should cause any Jew who is contemplating the worth of Christ and the New Covenant to realize his utter hopelessness to every attain perfection under the Old Covenant).

Hebrews 2:10 (note) For it was fitting for Him, for Whom are all things, and through Whom are all things, in bringing many sons to glory, to perfect the author of their salvation through sufferings (What sufferings? Certainly one would consider His temptation by Satan in the barren wilderness [see Mt 4:1-11, Lu 4:1ff, Mk 1:12, 13] and Gethsemane [Mt 26:36,44, Lu 22:39,44][in agony He was praying very fervently]). (Comment: This does not imply any moral imperfection in the Lord Jesus, but speaks of the consummation of the human experience of suffering the death of the Cross, through which He must pass if He is to become the Author or Captain of our salvation.)

Hebrews 5:9 (note) And having been made perfect, He became to all those who obey Him the source of eternal salvation,

Hebrews 7:19 (note) (for the Law made nothing perfect), and on the other hand there is a bringing in of a better hope, through which we draw near to God. (Comment: This means to carry through completely, to make complete, to finish, bring to an end. The old covenant could bring nothing to conclusion. The Mosaic economy could reveal sin but it could never remove sin, and so it had to be removed. It gave no security. It gave no peace. A man never had a clean conscience.)

Hebrews 7:28 (note) For the Law appoints men as high priests who are weak, but the word of the oath, which came after the Law, appoints a Son, made perfect forever.

Hebrews 9:9 (note) which is a symbol for the present time. Accordingly both gifts and sacrifices are offered which cannot make the worshiper perfect in conscience,

Hebrews 10:1 (note) For the Law, since it has only a shadow of the good things to come and not the very form of things, can never by the same sacrifices year by year, which they offer continually, make perfect those who draw near. (Contrast with Jesus in Hebrews 5:9 above.  The idea in Hebrews 10:1 is that the ceremonial law could not actually save the believer. Its work was always short of completeness.)

Hebrews 10:14 (note) For by one offering He has perfected  for all time those who are sanctified. (Comment: Wuest writes "Here, the completeness of the state of salvation of the believer is in view. Everything essential to the salvation of the individual is included in the gift of salvation which the sinner receives by faith in Messiah’s sacrifice. The words “for ever” here are to be construed with “perfected.” It is a permanent state of completeness in salvation to which reference is made. The words “them that are sanctified” are descriptive of the believer. He is one set apart for God) (ibid)

Hebrews 11:40 (note) because God had provided something better for us, so that apart from us they should not be made perfect.

Hebrews 12:23 (note) (But you have come...) 23 to the general assembly and church of the first-born who are enrolled in heaven, and to God, the Judge of all, and to the spirits of righteous men made perfect,

In sum the fundamental idea of telioo is the bringing of a person or thing to the goal fixed by God.

It is interesting and doubtless no mere coincidence that in the Septuagint (LXX) teleioo is translated numerous times as consecrated or consecration, especially speaking of consecration of the priests (cf Jesus our "great High Priest") (Ex 29:9, 29, 33, 35 Lv 4:5; 8:33; 16:32; 21:10; Nu 3:3). The LXX translators gave the verb teleioo a special sense of consecration to priestly service and this official concept stands behind the writer's use in this passage in Hebrews 5:9 (note). It signifies that Jesus has been fully equipped to come before God in priestly action.

All time (1336) (dienekes from dia = through + phéro = carry, bear) means carried through. It is used in the Greek idiomatic phrase "eis to dienekes" which means unlimited duration of time with particular focus upon the future, and therefore means always, forever, forever and ever, eternally, continually.

Under the LAW, the OLD COVENANT, it was MANY offerings, daily, time after time, year after year.

THE NIV GETS IT EXACTLY RIGHT, not the NASB. The NIV says,

"By one sacrifice he has made perfect forever THOSE WHO ARE BEING MADE HOLY."

"Are being made holy", that's exactly right. In the context of Hebrews "perfected" most likely refers to the fact that now we are fully cleansed from sin in contrast to the CEREMONIAL cleansing of the Old Covenant. The Law could make no one perfect (Heb 7:19, 7:11, 9:9, 10:1,2 cp Ro 8:3-4) and could never give the sinner a cleansed conscience, freeing him from consciousness of sins. What the Old could not do the New effected as shown to us by our Teacher the Holy Spirit in 10:16,17.

We are being brought to the full purpose (telos = goal) for which we were created...now in process but one day like Him for we shall see Him face to face (1Jn 3:2). Having this hope we make choices by which the Spirit purifies us daily from "glory to glory" (2Cor 3:18). (sanctified here is present tense and passive).

The passive voice indicates that this continual daily setting apart is BY GOD ("sanctifying work of the Spirit" 1Pe 1:2, 2Th 2:13, both primarily probably referring to "positional" sanctification but certainly not precluding His part in daily setting apart). But believer's do now have a responsibility to work out their salvation in fear and trembling (Php 2:12,13) as shown in 2Co7:1 (where the verb voice for cleanse is active subjunctive = possibility.)

Notice the recurrence of the favorite idea of perfecting. [Heb 2:10; 5:9; 6:1; 7:11, 19, 28; 9:9; 10:1, 14; 11:40].

All time - unlimited duration of time = w particular focus upon the future; always, forever, forever and ever, eternally

THOSE WHO ARE SANCTIFIED: tous hagiazomenous (PPPMPA): (2:11; 6:13,14; 13:12; Acts 20:32; 26:13; Romans 15:16; 1 Corinthians 1:2; Ephesians 5:26; Jude 1:1)

Passive voice = this process of progressively being set apart from the world & to God is coming from an outside Source (Jesus in Heb 2:11). 1Th 4:3 What this means is that you can know that you stand perfect in the eyes of your heavenly Father if you are moving away from your present imperfection toward more and more holiness by faith in his future grace. This truth is full of encouragement for imperfect sinners like us, and full of motivation for holiness. This means that you can have assurance that you stand perfected and completed in the eyes of your heavenly Father not because you are perfect now, but precisely because you are not perfect now but are "being sanctified", "being made holy", that, by faith in God's promises, you are moving away from your lingering imperfection toward more and more holiness. (See Heb10:32-35; 11:24-26 etc. for ex of how faith in future grace sanctifies.)

KJV Bible Commentary notes that here in Hebrews 10 where we see the verb sanctify (here and Hebrews 10:10) used twice the writer is describing...

the twofold nature of salvation (see Three Tenses of Salvation). The believer possesses a positional, judicial standing of righteousness and, second, a remaining need for practical, progressive holiness. Three factors within this verse make perfected absolute, suggesting the eternal security of the believer. The word itself (Greek teleioo from telos = goal) involves completion, the bringing of something to its end. Second, the use of the Greek perfect tense (have been sanctified -- see note Hebrews 10:10) suggests that the perfection has been accomplished and its effects are continuing. Third, the modifier, forever, expresses security for the believer.

The need, however, of a progressive sanctification is expressed by the word sanctified. The use of the present participle implies the thought of a sanctification that is continuing, rather than completed. There is an initial, or positional, sanctification involved in regeneration (1Cor 1:2; 6:1). Equally, there is a progressive sanctification by which the Holy Spirit continually maintains and strengthens the holiness imparted in regeneration (see note Romans 6:19; 2Cor 7:1; 1Thess 4:3). Finally, there exists for the people of God an ultimate or completed sanctification whereby we will be freed from even the very presence of sin within our lives (1Thess 5:23). Even though the believer’s sanctification is still in progress, yet because of Christ’s once-for-all sacrifice, he stands eternally secure and perfect because of Christ’s righteousness (2Cor 5:21). (Dobson, E G, Charles Feinberg, E Hindson, Woodrow Kroll, H L. Wilmington: KJV Bible Commentary: Nelson or Logos) (Bolding added)

Oswald Chambers writes on The Impartial Power of God