In the Tanakh, the idea of repentance is represented by two verbs: shuwb
{shoob} means to turn back and nacham
{naw-kham'} means to sigh, i.e. breathe strongly; by implication, to be sorry. Metanoeo
{met-an-o-eh'-o} is the Greek word used in the New Testament. It means to think differently or afterwards, i.e. reconsider. Repentance overcomes sin by changing hearts, attitudes, and actions that are rebellious to God's word.
Ezekiel 14:6: Therefore say unto the house of Israel, Thus saith the Lord GOD; Repent, and turn yourselves from your idols; and turn away your faces from all your abominations.
Ezekiel 18:30: Therefore I will judge you, O house of Israel, every one according to his ways, saith the Lord GOD. Repent, and turn yourselves from all your transgressions; so iniquity shall not be your ruin.
Mark 1:15: And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel.
Luke 13:1-5: There were present at that season some that told him of the Galileans, whose blood Pilate had mingled with their sacrifices. And Jesus answering said unto them, Suppose ye that these Galileans were sinners above all the Galileans, because they suffered such things? I tell you, Nay: but, except ye repent, ye shall all likewise perish. Or those eighteen, upon whom the tower in Siloam fell, and slew them, think ye that they were sinners above all men that dwelt in Jerusalem? I tell you, Nay: but, except ye repent, ye shall all likewise perish.
Acts 2:38: Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.
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;
Revelation 2:4-5:Nevertheless I have somewhat against thee, because thou hast left thy first love. Remember therefore from whence thou art fallen, and repent, and do the first works; or else I will come unto thee quickly, and will remove thy candlestick out of his place, except thou repent.
Revelation 3:19: As many as I love, I rebuke and chasten: be zealous therefore, and repent.