Eternal IN-securists ignore the greater context.
No. Merely accusation, without evidential support.
Again, you place a strawman on the field, since we teach scriptural assurance (even "earnest"), rather than presumptuous assurance. We are not "IN-secur[e]" in the least. Those who are truly "IN-secur[e]" are the OSASer's, who must redefine what it means to "believeth", so that they do not have to worry about falling away from Christ, and do not burden themselves with taking heed to themselves.
Back to our position. Those in Christ are indeed secure. Yet that security is conditional based upon an individuals "believeth". Remain in Christ by that "believeth", and Heaven is assured. Leave Christ by no longer "believeth", and Heaven is lost, for turning away from the real sacrifice, there remaineth no more sacrifice for sins, and to choose to go back out into sin is to be lost. For Jesus Christ is Eternal Life, and never is eternal life inherent with us, as texts already cited.
If the word 'sanctified' in Hebrews 10:29 is used to describe saved people who lost their salvation as eternal IN-securists teach, then we have a contradiction because the writer of Hebrews in verse 10 said "sanctified through the offering of the body of Jesus Christ once for all" (Hebrews 10:10) and in verse 14, we read, "perfected for all time those who are sanctified." (Hebrews 10:14)
Not at all. It is your understanding of Hebrews 10:10,14,29 that is in question, not the scripture, nor its perfectly defined statements, nor our position on any of those texts.
Hebrews 10:9-10 is in parallel to Hebrews 10:1-2, in contrast of type to anti-type:
Type:
Heb 10:1 For the law having a shadow of good things to come, and not the very image of the things, can never with those sacrifices which they offered year by year continually make the comers thereunto perfect.
Heb 10:2 For then would they not have ceased to be offered? because that the worshippers once purged should have had no more conscience of sins.
Heb 9:9 Which was a figure for the time then present, in which were offered both gifts and sacrifices, that could not make him that did the service perfect, as pertaining to the conscience;
Heb 9:14 How much more shall the blood of Christ, who through the eternal Spirit offered himself without spot to God, purge your conscience from dead works to serve the living God?
Anti-type:
Heb 10:9 Then said he, Lo, I come to do thy will, O God. He taketh away the first, that he may establish the second.
Heb 10:10 By the which will we are sanctified through the offering of the body of Jesus Christ once for all.
This is demonstrated by the very next verses:
Heb 10:11 And every priest standeth daily ministering and offering oftentimes the same sacrifices, which can never take away sins:
Heb 10:12 But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God;
Heb 10:13 From henceforth expecting till his enemies be made his footstool.
Heb 10:14 For by one offering he hath perfected for ever them that are sanctified.
Did you see the same words used in Hebrews 10:1,10,14 - "perfect", "perfected", "sanctified", "sacrifices", even in similar language in Hebrews 10:2,11 - "purged", "take away sins"?
It continues, in Hebrews 10:18, in summation, by the Holy Ghost:
Heb 10:18 Now where remission of these is, there is no more offering for sin.
Remission is forgiveness, and is having ones sins "purged", or "taken away from" them by the singular "Once" (Hebrews 10:2,10) Sacrifice of Jesus Christ. Yet, forgiveness is only the first half of the plan. Blotting out is the second half. Sins which are forgiven are not gone in entirety, they are only removed from the sinner, and placed under the blood of Jesus, until such time as they are blotted out, as the Sanctuary service required, in Leviticus 16 & 23, &c. Who took the sin of the world upon Himself? Jesus Christ. If Jesus took them, as scripture states, then He has them. This is the entire point of Hebrews 9:28,
Heb 9:28 So Christ was once offered to bear the sins of many; and unto them that look for him shall he appear the second time without sin unto salvation.
Notice when "salvation" "appears". Read the word "unto" carefully. Jesus is even now dealing with the covered sins, as our great High priest (Hebrews 10:21) in the Most Holy Place, see Daniel & Revelation. Thus it is written:
Heb 10:22 Let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience, and our bodies washed with pure water.
Notice the "faith" that needs to be present. Without "faith" it is impossible to please God. There are those that had "faith" at one time, and draw not "near", but "away from" Christ Jesus of their own volition, by submitting to temptation.
This is why Paul (Hebrews) warns strictly that it is entirely possible (not necessary -- the false strawman of OSASer's against us):
Heb 10:23 Let us hold fast the profession of our faith without wavering; (for he is faithful that promised;)
Heb 10:24 And let us consider one another to provoke unto love and to good works:
Heb 10:25 Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching.
Heb 10:26 For if we sin wilfully after that we have received the knowledge of the truth, there remaineth no more sacrifice for sins,
Heb 10:27 But a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries.
It is we that must "hold fast" "the profession of our faith" "without wavering", because by very definition, it is then possible to not "hold fast", and to not have the "profession of our faith" any longer, and to actually be "wavering" and so fall away. It is entirely possible to "forsake the assembling of ourselves together", for Paul even includes them, by saying, "as the manner of some is", and that among the believers, the "profess[ors] of our faith". Paul then states with clarity, that "if we" (the Christian) sin willfully (which is contrary to God's will, Hebrews 10:9-10), that is to choose to leave Christ Jesus behind, and no longer believe in the salvation offered in Him and the sanctification in Him, then there "remaineth no more sacrifice for sins" and we are naked, and without clothing, having abandoned the only clothing provided by God, by removing them from ourselves. Afterward, there is only "a certain looking for of judgment and fiery indignation" for those who once believed, but forsook the right way, and shall join with those "adversaries" who never believed. These people, if they choose to so forsake Christ Jesus, after having known Him, and received the knowledge (intimate knowing) of the Truth (Jesus Christ; John 14:6), then they loved to believe in a lie instead, and their faith when from Jesus to something else. Believeth is always the condition. God's promises are always faithful, but we must always "believeth" in that. It is our part to believe:
Joh_6:29 Jesus answered and said unto them, This is the work of God, that ye believe on him whom he hath sent.
Read the verses carefully. The Sanctified are only found in Christ Jesus. So long as a person believeth in Christ Jesus, they are sanctified (purged from their old sins, forgiven of their old sins), but if they leave off from Christ, their old sins are no longer forgiven (Matthew 18, &c), their old sins are no longer covered by the blood of the true Sacrifice, and they have no more sacrifice for their sins, and thus they can only look forward to dying with the adversaries, and thus it is worse for them, to have at one time known the way the truth and the life, and been in Him, and to have forsaken Him.
Thus, those accepting Christ Jesus are indeed "sanctified", purged from their old sins. Yet, those who forsake Him, have their sins placed back upon themselves (Matthew 18, &c). Thus cannot ever be saved after that.