Repentance

The Bible teaches that repentance is necessary for salvation.

Jesus said, "Except ye repent ye shall like wise perish" (Luke 13:1-5).
"And the times of this ignorance God winked at, but now commanded all men everywhere to repent" (Acts 17:30).
Jesus is "long suffering toward us, not willing that any should perish but that all should come to repentance" (II Peter
3:9).
Paul's mission that people would receive forgiveness (Acts 26:15-21).
Men should repent (Mark 6:12).
Necessary for sins to be blotted out and conversion (Acts 3:19).
Needed for life (Acts 11:18).
Peter's message on the day of Pentecost, "Repent, and be baptized everyone of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost" (Acts 2:38). Note that Peter said, "everyone"should repent and be baptized in the name of Jesus Christ.

The Bible teaches that John the Baptist and Jesus taught it as a basic requirement of entrance into the Kingdom of Heaven
(Matthew 3:2, 8;4:17).

It is necessary to be born of the water and spirit? (John 3:3-5).

How do I repent?

Feel after Him, seek Him, find Him (Acts 17:27).
Abide in Him (I John 3:36). Spend time with Him. Pray. Depend upon Him.
Believe that He is and that He is a rewarder of them that diligently seek Him (Hebrews 11:6).
Do what is possible to prove your change of heart. Leave the rest in God's hands.
Ask Him to help you overcome your unbelief (Mark 9:24).
Godly sorrow worketh repentance-heart sorrow (II Corinthians 7:9-11, Psalm 34:18; 51:17, James 4:9) Let the tears flow. If you are a man, crying is manly before God. Nothing cleanses like tears.
Be able to say, "not my will, but thine be done" (Luke 22:42). Surrender yourself to Jesus. Die out to yourself, your ways, your plans. Give yourself totally, unreservedly unto Jesus. Put your life on the altar. Lift your hands to him
Draw nigh to God, cleanse your hands, purify your hearts. Be troubled, mourn and weep.