But all born again believers overcome.
Jesus warns a church in Revelation to repent, and tells them
if they overcome, He wont erase their names from the book of life:
Rev 3:3 Remember therefore how thou hast received and heard, and hold fast, and repent. If therefore thou shalt not watch, I will come on thee as a thief, and thou shalt not know what hour I will come upon thee.
Rev 3:4 Thou hast a few names even in Sardis which have not defiled their garments; and they shall walk with me in white: for they are worthy.
Rev 3:5 He that overcometh, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels.
And this is the church that is claimed to be the reformed Church, yet Jesus starts off warning them they are dead, that most of them had defiled their white robes (which represent being righteous), and warned to repent - ending by telling them if they overcome, their names will remain in the book of life.
Overcoming is after salvation, and there’s no guarantee we will be an overcomer.
Pure white raiment (robes) are what the righteous saints are given, and are part of their wedding attire.
Rev 19:7 Let us be glad and rejoice, and give honour to him: for the marriage of the Lamb is come, and his wife hath made herself ready.
Rev 19:8 And to her was granted that she should be arrayed in fine linen, clean and white: for the fine linen is the righteousness of saints.
Rev 19:9 And he saith unto me, Write, Blessed are they which are called unto the marriage supper of the Lamb. And he saith unto me, These are the true sayings of God.
Believers get white robes, but can defile their robes - if they defile their robes, their names are blotted out of the book of life.
Most of those in the church at Sardis had defiled their white robes:
Rev 3:4 Thou hast a few names even in Sardis which have not defiled their garments; and they shall walk with me in white: for they are worthy.
Rev 3:5 He that overcometh, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels.
Jesus also warned some churches in Revelation that many of them had soiled their robes, and some had lost them completely, and were naked.
Rev 3:17 Because thou sayest, I am rich, and increased with goods, and have need of nothing; and knowest not that thou art wretched, and miserable, and poor, and blind, and naked:
Rev 3:18 I counsel thee to buy of me gold tried in the fire, that thou mayest be rich; and white raiment, that thou mayest be clothed, and that the shame of thy nakedness do not appear; and anoint thine eyes with eyesalve, that thou mayest see.
What’s sad is those church members in Revelation 3:17-18 were naked, but thought they were clothed.
They did something to defile their garments, that they mistakenly thought was ok with God.
In other words, they believed they could live a sinful life, and remain in Christ.
They were deceived by OSAS into thinking grace was a license to sin, with no eternal consequences.
Again, there’s no guarantee that believers will overcome, per Jesus’ warning to the churches in Revelation.