As with the OP, this is a loaded question which needs clarification. By "unrepentant" do you mean they knowingly committed these sins in the past, and were conscious of doing so and convicted of them yet never repented of such which Godly sorrow effects, and thus would knowingly willfully do so again, or even are doing so?
Or they did do such and did not realize it (for one, deceit is not always apparent, nor do we always recognize hypocrisy ourselves) or perhaps forgot about it (not in hardness of heart) before they realized guilt (do you remember every violation of what God commands, which can include civil laws?), but had a contrite heart that did not want to sin.
Or they are even struggling with a habitual sin, including world affections, yearning to find victory over it in the fear of God?
In the first case i believe the answer is they are presently headed to Hell, since this cognizant impenitence is inconsistent with saving faith and the contrite heart and holy life it effects.
And that God gives space to repent (Rv. 2:21) and works to bring his own to that place, (1Co. 11:32) and in which we can be instruments. (1Co. 5)
I believe King David somehow anesthetized his conscience regarding his own conduct during the time his great sins - and which ignorance is not the same as mere being unaware - but the moment he was convicted of his sins then he repented out of Godly sorrow.
And Christian faith is that of holding faith, and a good conscience, versus putting both away: "Holding faith, and a good conscience; which some having put away concerning faith have made shipwreck." (1 Timothy 1:19)
(Note that there is also such a thing as a believer being so scrupulous that that they constantly see themselves as sinful, and with the devil working to convince them they are lost and might as well live as such. If you doubt me, read the
tremendous back and forth struggle of John Bunyan in regard to assurance, which at length he obtained.)
As to the 2nd and 3rd, I see in Scripture that such are saved who have sins of ignorance or perhaps forgot about it, or were struggling with a besetting sin, but who have contrite heart that did not want to sin, and thus repent and ask God for forgiveness for sins they are convicted of, or would do so if they were.
And i am sure there are multitudes of sins we have committed that we are not aware of and never confessed every time we did so, but if we are not repentant in heart over them in general (and thus would confess them to God if we were realized them) then God will chasten us in order to deal with them.
For this is consistent with true faith, which is not rebellion but neither does it mean one must attain perfection of character, having victory over everything that in unholy in him, and thus never sin, though this is out of weakness, not willful knowingly impenitently sinning. I do not see this sinlessness in the 11 disciples of Christ whose names were written in heaven, (Luke 10:20) or in Peter or Paul.
Instead, it is not being sinless that obtains eternal life with God, but repentant faith, (Acts 3:19) the faith which effects obedience, includes repentance when convicted of doing so, and
which "the Lord is nigh unto them that are of a broken heart; and saveth such as be of a contrite spirit" (Psalms 34:18) refers to.
Thus the reason the obedient (as described) are saved is because they are of true faith, manifested by obedience thru the Spirit, not because they have become perfect in character, while the reason the obedient are damned is because they are not of faith, not because they are not as good as believers (indeed, some may have more light and character and be better than some ignorant believers of weak character).
But relative to light and grace given (which the Righteous Judge does take into account) I largely basically agree with how J. C. RYLE - 1816-1900 describes this faith of the regenerate in
"Are you born again?"
"Whosoever is born of God doth not commit sin;" and again, "Whosoever is born of God sinneth not." - 1John 3:9; 5:18.
A man born again, or regenerate, does not commit sin as a habit. He no longer sins with his heart and will and whole inclination, as an unregenerate man does. There was probably a time when he did not think whether his actions were sinful or not, and never felt grieved after doing evil. There was no quarrel between him and sin; they were friends. Now he hates sin, flees from it, fights against it, counts it his greatest plague, groans under the burden of its presence, mourns when he falls under its influence, and longs to be delivered from it altogether. In one word, sin no longer pleases him, nor is even a matter of indifference; it has become the abominable thing which he hates. He cannot prevent its dwelling within him. If he said he had no sin, there would be no truth in him (1 John 1:8). But he can say that he cordially abhors it, and the great desire of his soul is not to commit sin at all. He cannot prevent bad thoughts arising within him, and short-comings, omissions, and defects appearing, both in his words and actions. He knew, as James says, that "In many things we offend all" (James 3:2). But he can say truly, and as in the sight of God, that things are a daily grief and sorrow to him, and that his whole nature does not consent unto them.
That you even ask me this evidences that you have not read the few posts (as
here) I made on this thread, and even the
one to you in which i said
"this saving justifying faith, is a faith which effects obedience by the Spirit in word and in deed, in heart and in life, whereby "the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit, (Romans 8:4) insofar as we do.."
And to Kenny'sID:
Conversely, to practice unrighteousness, versus characteristic obedience by the Spirit who enables and motivates it (thus only God really deserves any credit) testifies to unbelief, thus having no covering for sin, leaving such damned, either never having come to faith or having an "an evil heart of unbelief, in departing from the living God," (Hebrews 3:12) or via a false gospel. (Galatians 5:1-5)
In short, the answer to your question is NO.
This also needs clarification. Do you mean unrepentant, unconfessed known sin by impenitent "believers" and thus would knowingly willfully do so again, or even are doing so as in the first category i described in response to #1? Then the answer is already given there (forfeiting what faith obtained, if they were believers once).
For those of true repentant faith then there sins will not send them to Hell, for these are of faith, thus they characteristically practice righteousness, and repent when convicted of not doing so, and in essences are repentant of sins of ignorance.
And since the basis for their justification is not being sinless, but faith which purifies the heart (Acts 15:9) and is counted for righteousness, then while repentant confessing of sin is consistent with that faith, yet sins of ignorance, and imperfection of character is not going to damn them if they are of repentant faith.
And if the condition for justification is sinlessness, and needing to confess every sin you have, or else be damned, then so will having sinful character defects.
Yet the mature man of God means seeking to be as Christ in all aspects of character, which Paul yearned for personally, looking forward to the day when "this corruptible must put on incorruption," (1 Corinthians 15:53) "Who shall change our vile body, that it may be fashioned like unto his glorious body, according to the working whereby he is able even to subdue all things unto himself," (Philippians 3:21) while seeking to presently be as much as a resurrected believer as he could be, which is what I these expressing:
Not as though I had already attained, either were already perfect: but I follow after, if that I may apprehend that for which also I am apprehended of Christ Jesus. (Philippians 3:12) I press toward the mark for the prize of the high calling of God in Christ Jesus. (Philippians 3:14)
And i sadly have a l o n g way to go in that.
I think I just answered that with my last remark (made before I read this). However, 2 Peter 1 does tell us how we can becoem mature enough that we will never fall. Not there yet myself, sadly.
Because it seemed you might be confusing the effect of faith (holiness, works) with the actual cause of justification (faith which effects works) and which is consistent with Catholic teaching in which the effect of regeneration holiness is what formally justifies a person, and which means he must have this condition (which becomes not simply being forgiven but perfection of character) to enter Heaven, thus necessitating the invention of RC purgatory, which my comments addressed.
Here James 2 if often invoked as regard works justifying, but which they justify the believer as being one of saving faith, if it is by works that God imputes righteousness (versus effectual faith which results in practical righteousness) - which is what Paul is dealing with in Romans 4 - then James is contradicting both Moses (Genesis 15:6) and Paul.
Yet Paul also teaches that it is those of obedient faith which shall be justified. (Romans 2:13)
Hope this helps, if not infallible.