In regards to Hebrews 10:26, To "sin willfully" carries the idea of deliberate intention that is habitual, which stems from rejecting Christ deliberately. This is continuous action - a matter of practice. Now we don't walk along our daily life and "accidentally" fall into a pit called sin. We exercise our will but, the use of the participle clearly shows continuous action. The unrighteous practice sin (1 Corinthians 6:9-10; Galatians 5:19-21); not the righteous, who are born of God. (1 Corinthians 6:11; 1 John 3:9)
In context, the writer is addressing unbelieving Hebrews who fail to enter into the new covenant of grace by faith and receive God’s forgiveness through the blood of Jesus. If these Hebrews reject the new covenant of grace God established through the blood of Jesus and, instead, depended upon the works of the old covenant of law to rescue them from the coming judgment, then they could only expect to be consumed in judgment as an enemy of God.
Hebrews 10:26 (AMPC) - For if we go on deliberately and willingly sinning after once acquiring the knowledge of the Truth, there is no longer any sacrifice left to atone for [our] sins [no further offering to which to look forward]. 27 [There is nothing left for us then] but a kind of awful and fearful prospect and expectation of divine judgment and the fury of burning wrath and indignation which will consume those who put themselves in opposition [to God]. 28 Any person who has violated and [thus] rejected and set at naught the Law of Moses is put to death without pity or mercy on the evidence of two or three witnesses. 29 How much worse (sterner and heavier) punishment do you suppose he will be judged to deserve who has spurned and [thus] trampled underfoot the Son of God, and who has considered the covenant blood by which he was consecrated common and unhallowed, thus profaning it and insulting and outraging the [Holy] Spirit [Who imparts] grace (the unmerited favor and blessing of God)?
HEBREWS—NOTE ON 10:26–39 Warnings against Shrinking Back. The author
warns of the impending judgment upon those who willfully reject the faith. Yet
his purpose is to exhort the readers in their faith, a faith that he affirms based
on their past perseverance.
HEBREWS—NOTE ON 10:26–27 sinning deliberately. Willfully sinning and
refusing to repent. after receiving. The author refers especially to people
within the Christian community, who have thus heard the truth. The fact that
they “go on sinning deliberately even after receiving knowledge of the truth”
indicates that the people in view are not (and never were) genuine believers;
that is, these are people who have never genuinely embraced the gospel in a
way that has resulted in a life of faith, obedience, and the bearing of fruit. no
longer remains a sacrifice for sins. This could refer to the inability of willful,
unrepentant sinners to be restored (see 6:4–6), or more likely to the fact that
there is no place for them to turn for forgiveness outside of Christ’s sacrifice—
which they have rejected.
judgment. All people face judgment (see 9:27–28),
and apart from Christ’s sacrifice his adversaries receive eternal damnation.
These verses, then, function as a means used by God to call genuine Christians
to faith, obedience, and perseverance; and, if there is no evidence of fruit in
one’s life, to challenge such people to give fearful consideration as to whether
they are in fact genuine believers.
HEBREWS—NOTE ON 10:28–29 These verses argue from the lesser to the greater
(cf. 2:1–4; 9:14). In the Mosaic law, the death penalty comes upon those who
blaspheme God or who worship other deities (e.g., Lev. 24:13–16; Deut. 17:2–
7), so in the superior new covenant the expectation of judgment would be even
stronger. How much worse punishment … will be deserved by the one who
… ? The description that follows is of a person who has deliberately,
consciously, and persistently deserted “the living God” (cf. Heb. 3:12; 10:31;
12:22), renouncing Christ and the community of faith (6:4–8).
It is a
description of outright apostasy, involving a person who has done three specific
things: (1) trampled underfoot the Son of God, (2) profaned the blood of
the covenant, and (3) outraged the Spirit of grace. Such rejection of the
knowledge of the truth (10:26) through willful disobedience is tantamount to
trampling upon God’s Son, reckoning his blood to be defiled, and insulting the
Spirit who has offered such grace; the one who does this deserves eternal
judgment (v. 27). Some have argued that the statement by which he was
sanctified (Gk. hagiazō, “set apart,” “sanctify”) indicates that the person in
view here was a true believer (see note on 3:14, however, indicating a
fundamental difficulty with this view). Given the immediate context, it seems
most likely that “he was sanctified” should be understood in the sense of
someone who had been “set apart” or identified as an active participant in the
Christian community of believers, but who has subsequently committed
apostasy by renouncing his identification with other believers, by denying the
“knowledge of the truth” that he had heard, and by repudiating the work and
the person of Christ himself. Such a person’s apostasy is thus evidence that his
identification with the Christian community was only superficial and that he
was not a genuine believer. Another view is that the author is confident that the
grave warning in these verses will be the means by which those who are truly
elect will be braced to persevere in faith and obedience, and so to be saved (see
note on 6:4–8).