Repentance is a turning from sin to God (Deut 30:1-2; 2 Chron 6:26-27; 7:14; Neh 1:9; Ps 78:34; Isa 55:7; Jer 8:6; 31:18-19; Ezek 18:21; Mal 3:7; Matt 11:20-21; Luke 15:7; 16:30; Acts 3:19; 8:22; 14:15; 26:19-20; Rev 9:20-21). The open demonstration of this turning to God is sometimes called conversion (Acts 15:3; cf. 26:17-18; 1 Thess 1:9-10). Jesus and the New Testament preachers commanded people to repent, because without repentance there can be no salvation (Matt 3:2; 4:17; Mark 6:12; Luke 5:32; 13:3; 24:47; Acts 2:38; 11:18; 17:30).
It is true that faith is the means by which people receive salvation (Rom 3:22-25; Eph 2:8), but faith that does not involve repentance is not true faith. It is not a faith that leads to salvation. Faith means complete trust in Jesus Christ and his atoning death. It means that people must have total dependence on Christ for their entire salvation (see FAITH). But such trust is impossible so long as they cling to anything of themselves. They cannot rely upon the work of Christ for the forgiveness of sin unless they turn from that sin (Mark 1:15; Acts 11:21; 20:21; 26:18; 1 Thess 1:9).
Because faith involves repentance and repentance involves faith, the Bible in some places speaks of forgiveness as depending on faith (Acts 10:43; 13:38-39), in others as depending on repentance (Luke 24:47; Acts 3:19,26). But the preaching of repentance, like the preaching of faith, must be related to the death and resurrection of Jesus Christ (Luke 24:46-47). Although it is true that people must exercise faith and repentance if they are to be saved, it is also true that neither faith nor repentance would be possible in the heart of self-centred human beings apart from the gracious work of God. God is the one who brings conviction of sin within people and gives them the readiness to repent and believe (Acts 5:31; 11:18; cf. John 6:65; 16:7-11).
Repentance involves a complete change in the mind and will of the believer. It is more than mere sorrow for sin; it is surrender to God. People may be sorry for their sin because of its consequences, but still have no thought for God. True repentance recognizes the character of sin as deserving God’s judgment, and turns from that sin to ask God’s forgiveness. Sorrow for sin that ignores God leads only to self-pity and despair. Godly sorrow leads to repentance and new life (2 Cor 7:9-10; cf. Job 42:5-6; Ps 51:1-17; Luke 18:13). It proves its genuineness in a complete change of behaviour (Luke 3:8-14; 19:8; 2 Cor 5:17; 1 John 2:4-6). A different usage of the word ‘repent’ is found in the Old Testament, where writers sometimes use it in relation to God. The word simply has to do with a change in God’s dealings with people. It has nothing to do with any divine sin or failure (Gen 6:6; 1 Sam 15:11; Jer 18:7-10; Jonah 3:8-9; cf. Ps 110:4; Jer 4:28).