Letting go of resentment is better.

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Being God's reflection as a merciful person can be difficult to put into practice, but living with resentment and anger is far worse.

29 Let no corrupting word proceed out of your mouth, but only what is good for necessary edification, that it may impart grace to those who hear. 30 And do not grieve the Holy Spirit of God, by whom you were sealed for the day of redemption. 31 Let all bitterness, wrath, anger, clamor, and evil speaking be put away from you, with all malice. 32 But be kind to one another, tenderhearted, forgiving one another, just as God in Christ forgave you.

Ephesians 4:29-32

Showing mercy to those who have caused us some kind of harm is something that is not usual, that is to say: it is not natural, it is normal that we get angry with them and have resentment on many occasions, but God commands us to be merciful. As we have received God's mercy and abundant grace, we too must practice a merciful lifestyle of forgiveness.

Be therefore merciful, as your Father is merciful.

Luke 6:36

The great question is: why don't we put this lifestyle into practice? There are many times when there is a stone in the middle and it is called pride, we get angry when someone attacks us with something, such as disrespecting us or simply ignoring us. I am sure that at some point in your life you also went through a situation in which you were treated unfairly and were very hurt, we fill our minds with thoughts of suffering and we get caught up in it, we lose sight of the possibility of forgiveness.

All this generates resentment and brings with it negative consequences generally everything we do not want such as broken relationships, ties, emotional and physical problems and even indifference with the Lord. The longer we remain in that suffering, the more we do not eat anger and resentment, all this affects our relationship with ourselves and with the people around us, it also affects our communion with God, but not on the part of God towards us.

Forgiving is a simple act but we as human beings and according to our sinful nature find it very difficult. Even so, and with more reasons, nothing is justifiable to deny mercy to different people even to those who have harmed us or done us wrong. God calls us and motivates us to forgive just as he forgives us when we were enemies and let us always remember that with the help of his Holy Spirit we will be able to do it and have the habit of carrying it out.