Repentance means to feel great sorrow and remorse for your sins. You are heartbroken that you have sinned against God, who loves you so much. It is a Godly sorrow that truly WANTS to turn from sin and forsake it. It means confessing your sin, changing your behavior, and going in a new direction, which will result in a change in the way you live.
Repentance is a key element to salvation and a new life in the Bible.
(Acts 3:19) Repent ye therefore, and be converted, that your sins may be blotted out, when the times of refreshing shall come from the presence of the Lord;
(2 Cor 7:10) For Godly sorrow worketh repentance to salvation not to be repented of: but the sorrow of the world worketh death.
(Lk 13:3,5) I tell you, Nay: but, except ye repent, ye shall all likewise perish.
(Mt 4:17) From that time Jesus began to preach, and to say, Repent: for the kingdom of heaven is at hand.
(Acts 11:18) When they heard these things, they held their peace, and glorified God, saying, Then hath God also to the Gentiles granted repentance unto life.
(2 Pet 3:9)(Mk 1:15)(Lk 5:32)(Ezek 18:30)(Acts 17:30)(Acts 20:21)(Rom 2:4)(Mk 6:12)(Prov 28:13)(Ezek 14:6)