Acts 3:8: Bring forth therefore fruits meet for repentance.
If anyone is in Christ, he is a new creature. The old things have gone and the new has come. What happens to us when we repent of our sins and get baptized? The Holy Spirit comes and dwells in us and makes our hearts His home. Our lives get transformed by the power of the Holy Spirit.
This change does not happen overnight. It is a conscious, every day effort and process to change into the image of God and to be like Him. We have to bring forth fruits that are right for repentance. Just like how a tree is known by its fruits, in the same way people look at our lifestyle and read Christ in us. We are the living word of God for the world to read from. There should be no place for anger, strife, jealousy, hatred, bitterness, etc., in our lives. These have to be overwritten with the fruit of the Holy Spirit. This is what is meant by old things passing away and we becoming new in Christ. Repentance of sins leads us to newness in our life and in our walk with Christ.
The more we lean on God for a change in our life, the more God will help us change. God sees our heart and its willingness to comply with His word. There has to be a complete change in our heart which will lead to an outward display of God’s character. A complete change in our attitude, our behaviour, our speech, etc., will happen only if we are willing to bring out the proper fruits of repentance and feed on His word everyday.