first of all to your last question, a true believer is one who has repented and trusted in Christ alone for salvation.
like the scripture i’ve noted if a person is a true believer walking in the light of Christ and sins will stand convicted by the Holy Spirit and will confess their sins to God.
God Bless
JL; As a Catholic I can know if I am in a state of grace and on the road to eternal life at anytime, by examining my conscience, in light of Christ’s teaching taught by his Church. right now I am in grace. However, I have no absolute assurance that I will perserver to the end. I have confidence I will and I have absolute assurance that Christ will provide the way and grace for me to overcome any temptation, but I have free will at all times to choose life or death, this day or any other day. I also have absolute assurance if I willfully sin in a serious matter, losing the life of God within (the indwelling of the Holy Spirit), and repent (sorrow and intention to sin no more) and confess I will be cleansed by the blood of Christ and restored to life in Christ. One cannot willfully commit adultery and expect the life of God to remain within, when one has freely choosen death orver life, the soul that sins will die spiritually.
Joh 6:47 Verily, verily, I say unto you, He that believeth hath eternal life. Yes but, 1 Corinthians 10:12 Therefore let any one who thinks that he stands TAKE HEED LEST HE FALL.
JN 6:54 He that eateth my flesh and drinketh my blood hath eternal life: and I will raise him up at the last day. Yes but, 1Cor 11:29 For he that eateth and drinketh unworthily, eateth and drinketh damnation to himself, not discerning the Lord’s body.
JN 10:28 and I give unto them eternal life; and they shall never perish, and no one shall snatch them out of my hand. 29 My Father, who hath given [them] unto me, is greater than all; and no one is able to snatch [them] out of the Father`s hand. Yes but, Galatians 5:1,4 . . . stand fast therefore, and do not submit AGAIN TO a yoke of SLAVERY . . . You are severed from Christ, you who would be justified by the law; YOU HAVE FALLEN AWAY FROM GRACE.
Ga 6:8 For he that soweth to his flesh shall of the flesh reap corruption; but he that soweth to the Spirit shall of the Spirit reap life everlasting. Yes but, Ga 3:3 Are ye so foolish? Having BEGUN IN THE SPIRIT, are ye now made perfect by the flesh? Hb 3:12-14 Take care, brethren, lest there be in any of you an evil, unbelieving heart, leading you TO FALL AWAY FROM THE LIVING GOD. But exhort one another every day . . . that none of you may be hardened by the deceitfulness of sin. For WE SHARE IN CHRIST, IF ONLY WE HOLD our first confidence FIRM TO THE END.
Tit 1:2 In hope of eternal life, which God, that cannot lie, promised before the world began; Yes but, 1 Timothy 4:1 Now THE SPIRIT EXPRESSLY SAYS that in later times SOME WILL DEPART FROM THE FAITH by giving heed to deceitful spirits and doctrines of demons. 1 Tm5:15 For SOME HAVE already STRAYED AFTER SATAN.
1Jn5:13 These things have I written unto you that believe on the name of the Son of God; that ye may KNOW that ye have eternal life, and that ye may believe on the name of the Son of God. Yes but, Philippians 3:11-14 that if possible I may attain the resurrection from the dead. NOT THAT I HAVE ALREADY OBTAINED THIS OR am already PERFECT; but I PRESS ON to make it my own, because Christ Jesus has made me his own. Brethren, I DO NOT CONSIDER that I HAVE MADE IT MY OWN . . . I PRESS ON TOWARD THE GOAL for the prize of the upward call of God in Christ Jesus. 1 Corinthians 9:27 but IPOMMEL MY BODY and subdue it, LEST after preaching to others I MYSELF SHOULD BE DISQUALIFIED.
2 Peter 2:15,20-21 FORSAKING THE RIGHT WAY THEY HAVE GONE ASTRAY; they have followed the way of Balaam, . . . For if, after they have escaped the defilements of the world THROUGH THE KNOWLEDGE OF OUR LORD AND SAVIOUR Jesus Christ, THEY ARE AGAIN ENTANGLED in them AND OVERPOWERED, the last state has become worse for them than the first. For it would have been BETTER FOR THEM NEVER TO HAVE KNOWN THE WAY of righteousness than AFTER KNOWING it to TURN BACK from the holy commandment delivered to them.
Jms 5:19 My brethren IF any ONE among you WANDERS FROM THE TRUTH and some one brings him back 20 let him know that whoever BRINGS BACK A SINNER from the error of his way WILL SAVE HIS SOUL from death and will cover a multitude of sins If one has assurance of salvation how could his soul be saved from death by one who BRINGS HIM BACK FROM SIN to repentance. If he is BROUGHT BACK he had to be in grace before he sinned