The Apostle Paul, using the present tense in writing Romans 7:15-25, stated that he was struggling as a result of a battle between the influence of his flesh (the sin nature with which he was born as a child) and the influence of the indwelling Holy Spirit (his born again nature).
In addition, the Apostle John wrote: "If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, He is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness. If we say we have not sinned, we make Him a liar, and His Word is not in us" (1 Jn. 1:8-10).
James, commonly accepted as the brother of Jesus and head of the Jerusalem Church (Acts 12:2; 15:13; 21:18; 1 Cor. 15:7; Gal. 1:9; 2:9, 12), spoke of born again believers, who were ill, confessing their sins that they might be forgiven and healed (Jam. 5:13-20).
So what should the born again believer do when he or she sins? I recently heard a sermon that made these three points:
1) Admit you have sinned. A believer will immediately Regret sinning.
2) Abhor your sin. A believer will have Remorse over his or her sin.
3) Abstain from repeating the sin. A believer will Repent (turn from that sin).
The reason I am writing this, is because many young believers become discouraged when they seem to continually "mess up." A large number actually believe they have lost their salvation because they sinned. That is not true. The Word says that those who are saved are "sealed" by the Holy Spirit (Eph. 1:13; 4:30). God's Word also says that "He which hath begun a good work in you will perform it until the day of Jesus Christ" (Phil. 1:6). HE WILL DO IT!
Do not be discouraged when you fail as a believer;
He who has begun a good work in you never fails!