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I have already received Jesus Christ as the only and sufficient Savior, I have repented of all my past sins, is repentance necessary in my life even though I am already a child of God?
He who covers his sins will not prosper;
But he who confesses and forsakes them will have mercy.
14 Blessed is the man who always fears God;
But he who hardens his heart will fall into evil.
Proverbs 28:13-14
We understand that it is necessary to confess our sin, the word of God tells us that God is just and faithful to forgive absolutely all our sins and it does not end like that, he also cleanses us from all evil, perhaps in the next verse we will not find the word repentance but we can see this topic a little deeper.
9 If we confess our sins, he is faithful and just to forgive our sins, and cleanse us from all evil.
1 John 1:9
Let us remember that when we talk about repentance, we are talking about having a new mind, leaving behind past practices and turning to new actions, new ways of thinking and in this way we have new results. For those who have not known God, for them repentance is more focused on that saving faith by deciding to put their trust in Christ and be born again. But for those who have already been born again, for those of us who are children of God and believe in Him, repentance means a transformation, a change of heart. This is not an action with an instant result like magic. Repentance is an attitude that we incorporate as we get to know God, that is to say: we lead a life according to the word of God, according to the way of Christ.
The text we have seen in John, when it speaks of "confessing" is speaking of coming to an agreement with, in these cases if we confess our sins, our faults to God it means that we are coming to an agreement with him about that situation. Although here the confession and repentance does not refer to the aspect of salvation, it implies that God transforms our mind and our heart continuously molding us according to the image of his son time after time. Here that part is fulfilled in which the word of God is like a mirror in which we reflect ourselves, the word of God is transforming our life and each time we are being transformed into the image of Jesus Christ.
All this implies a progressive change of attitude and rejection of those patterns that at another time were not common, that which represents the difficulty of spiritual development in our life, we are leaving it aside to grow spiritually with Jesus Christ, day after day we look more and more like our model, Jesus.
Are there sins or situations that are becoming very difficult to bear? This is where we must apply confession and repentance to give that place to God and man, transforming our minds and hearts into the image of his Son.