The answer is "Of course not."
A Christian will not remain impenitent, and one who remains impenitent was not a Christian.
However, all Christians will Persevere until the end because ...
- [Romans 8:29-30 NASB] 29 For those whom He foreknew, He also predestined [to become] conformed to the image of His Son, so that He would be the firstborn among many brethren; 30 and these whom He predestined, He also called; and these whom He called, He also justified; and these whom He justified, He also glorified.
- [Philippians 1:6 NASB] 6 [For I am] confident of this very thing, that He who began a good work in you will perfect it until the day of Christ Jesus.
- [John 6:44 NASB] 44 "No one can come to Me unless the Father who sent Me draws him; and I will raise him up on the last day.
- [Ephesians 1:3-14 NASB] 3 Blessed [be] the God and Father of our Lord Jesus Christ, who has blessed us with every spiritual blessing in the heavenly [places] in Christ, 4 just as He chose us in Him before the foundation of the world, that we would be holy and blameless before Him. In love 5 He predestined us to adoption as sons through Jesus Christ to Himself, according to the kind intention of His will, 6 to the praise of the glory of His grace, which He freely bestowed on us in the Beloved. 7 In Him we have redemption through His blood, the forgiveness of our trespasses, according to the riches of His grace 8 which He lavished on us. In all wisdom and insight 9 He made known to us the mystery of His will, according to His kind intention which He purposed in Him 10 with a view to an administration suitable to the fullness of the times, [that is,] the summing up of all things in Christ, things in the heavens and things on the earth. In Him 11 also we have obtained an inheritance, having been predestined according to His purpose who works all things after the counsel of His will, 12 to the end that we who were the first to hope in Christ would be to the praise of His glory. 13 In Him, you also, after listening to the message of truth, the gospel of your salvation--having also believed, you were sealed in Him with the Holy Spirit of promise, 14 who is given as a pledge of our inheritance, with a view to the redemption of [God's own] possession, to the praise of His glory.
- [Philippians 2:13 NASB] 13 for it is God who is at work in you, both to will and to work for [His] good pleasure.
The Christian will not persevere if he does not conditionally repent of his sins. The Jews were once God's chosen yet because of their "impenitent heart" (Romans 2:5) they were cast off (Romans 11). Not one of the verses cited above says the Christian will persevere if he does not repent.
Revelation 3:1-5 the church at Sardis had become spiritually dead and told to repent or they would be blotted out of the book of life.
Revelation 2:1-5 if the church at Ephesus did not repent, then their candlestick (church at Ephesus) would be removed, God would no longer recognize them as His church.
The verses you cited above describes the group called Christian.....it is the group that is sealed, justified, sanctified, holy and without blame. Therefore anyone who becomes a Christian takes on these traits. These traits only belong to the group, NOT the individual apart from the group. So if a Christian will not repent of his sins, he will fall from the group and no longer possess these traits while the group remains saved. A Christian then must CONDITIONALLY remain in the group to possess these traits. There is no unconditional guarantee for one who becomes a Christian he will faithfully remain in the group and possess these traits, thus the NT is full of admonitions, warnings, heedings about remaining faithful else one will fall away.
Just a few verses (of dozens) that warn about falling away from the group, no longer possess the groups traits and become lost:
1 Timothy 4:1 - Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils;
Hebrews 6:4-6 - For [it is] impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,....and then have fallen away, to restore them again to repentance, since they are crucifying once again the Son of God to their own harm and holding him up to contempt.
Hebrews 3:12-19 - Take heed, brethren, lest there be in any of you an evil heart of unbelief, in departing from the living God.
Revelation 2:4-5 - Nevertheless I have [somewhat] against thee, because thou hast left thy first love.
2 Peter 2:20-22 - For if after they have escaped the pollutions of the world through the knowledge of the Lord and Saviour Jesus Christ, they are again entangled therein, and overcome, the latter end is worse with them than the beginning. ….. What the true proverb says has happened to them: “The dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire.”
Romans 11:19-22 - Thou wilt say then, The branches were broken off, that I might be graffed in.