The word repentance in the New Testament is the Greek word metanoia, and it means change mind. Even God repented in scripture, changed His mind (Genesis 6:6-7 and 1 Samuel 15:11).
Strongs Greek – 3341 – metanoia
Definition: change of mind, repentance Usage: repentance, a change of mind, change in the inner man.
When Jesus says, “repent and believe the gospel,” He is saying, change your mind from unbelief to belief about who I am and what I have done for you.
Repentance and a change in belief are not separate events and happen with one flip of the coin from unbelief to belief. The two are inseparable. When we changed our mind from unbelief to belief in Jesus, we were repenting and changing what we believed in the same moment, most not even realizing that was repentance.
Repentance is going on all the time in the life of a Christian as they believe more and more of what God’s word states. It is going on all the time in church’s even if the word repentance is never preached. The lost are hearing the message and coming to a saving knowledge of Christ. Believers in the gospel are hearing the word and beginning to believe they are a new creation in Christ, and the old has passed away, just as the Bible states. This is repentance, a change in one's mind, in one's belief.
Also in perfect sync with changing our mind to believe in salvation by faith alone, the word clearly tells us that it is foundational teaching, to repent, change our mind, not from our outward acts of sin, but from the dead works of trying to be right with God through the law and good works. We fully replace the thought of earning our salvation, with a new belief, salvation by faith in Christ alone.
Good works are a fruit and not a root of our salvation.
Therefore leaving the elementary teaching about the Christ, let us press on to maturity, not laying again a foundation of repentance from dead works and of faith toward God, Heb 6:1 NAS
That said, when we change our mind from unbelief to belief, we are repenting from the one unforgivable sin of unbelief in Jesus as the only way to eternal life. Now with Jesus in our life, the love of Christ constrains and compels us to do living works and the next right thing, instead of being motivated by the fear of punishment and guilt.
Many more New Covenant Bible Studies HERE. Jesus poured out His blood for the New Covenant of grace and truth, replacing the Old Covenant law of Moses. Believers are exclusively under the New Covenant, the last will and testament of Jesus that began after the cross.
And in the same way He took the cup after they had eaten, saying, "This cup which is poured out for you is the new covenant in My blood. Luke 22:20