Repentance is the first step in obeying the Gospel of Jesus Christ. Jesus said:
Repent, for the kingdom of heaven is at hand (Matthew 3:2 ESV).
No, I tell you; but unless you repent, you will all likewise perish (Luke 13:3 ESV).
The other steps in obeying the gospel are baptism in the name of Jesus Christ for the remission of sins and being filled with the Holy Ghost, with the evidence of speaking in tongues (Acts 2:38, Acts 2:4)
much more than wanting to change from an undesirable behavior and lifestyle to a
better and wholesome lifestyle, which is a good thing but is about one being reformed only. Whereas repentance is actually about being changed, transformed, converted and turned completely to Jesus Christ.
Let’s use this fictitious story to illustrate the difference:
“Suppose I am a thief and have committed many robberies and have not been caught as I am good at what I do and I am an unknown subject at large. Then one day, out of the blue I decide that I don’t want to live like this, I want to reform and change how I live. I turn myself in to the authorities. They tell me that is commendable that I have turned myself in and want to reform but, unfortunately, there wasn’t anyone who could pardon me, who would forgive me of past. I wasn’t at all surprised, I knew that would be the case. While in prison, I never felt good about being reformed, until the day I repented.
One Sunday I attended the prison church where I heard the Gospel of Jesus Christ preached. By the end of the sermon, I was sorrowful, I fell to my knees and for the first time in my life tears started running down my cheek as I thought about my life and that I really wanted to change, that I really wanted to turn to God. I repented to God, confessing my sins and I asked Jesus to forgive me. I felt God touching my heart. I realized that God was right there forgiving me. What a feeling! I was free of from the guilt and shame from my past even though I still needed to finish my prison sentence but I knew I wasn't going to perish.”
Of course this illustration lines up with scripture.
Paul wrote that it is Godly sorrow will cause us to repent whereas worldly sorrow – reformation – produces death i.e. worldly sorrow does not lead you to an eternal life with the Lord Jesus Christ.
For godly sorrow produces repentance leading to salvation, not to be regretted; but the sorrow of the world produces death (2 Corinthians 7:10 NKJV).
Luke wrote that without repenting you cannot be changed, or converted:
Repent therefore and be converted, that your sins may be blotted out, so that times of refreshing may come from the presence of the Lord (Acts 3:19 NKJV).
Peter said that Jesus does not want anybody to perish:
The Lord is not slow to fulfill his promise as some count slowness, but is patient toward you, not wishing that any should perish, but that all should reach repentance (2 Peter 3:9 ESV).
In the illustration I used the sin of theft but it could be anything - lying, cheating, pride, lust, adultery, sexual immorality, drunkenness, taking God's name in vain - really anything that you know deep down is not pleasing to God.
Repentance is the first step to salvation and that happens when the person seeking God obeys the Gospel of Jesus Christ and is born again. Notice in the following verse Jesus is saying that "believers" will repent:
And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel (Mark 1:15).
After one is born again, there will be times when further repentance will be required. God does not want us to return to our sinful ways but if we repent with Godly sorrow, He will forgive us.
Therefore tell the people: This is what the Lord Almighty says: ‘Return to me,’ declares the Lord Almighty, ‘and I will return to you,’ says the Lord Almighty (Zechariah 1:3).
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 that we have not sinned, we make him a liar, and his word is not in us (1 John 1:8-10 ).