If you forgive others their transgressions, your heavenly Father will forgive you. But if you do not forgive others, neither will your Father forgive your transgression. (Mt 7,14-15)
Prayer is one of the religious activities of any religion. In fact every religion teaches its members to pray. That is why even the disciples of Jesus asked Jesus to teach them prayers. But Jesus did not give them many prayers. In fact he criticized long prayers or prayers of many words (Mt 7,6).
We know well that Jesus prayed and prayed often. He was going early in the morning to pray and there were days in which he spent the whole night in prayer. But what he prayed is not known much. His prayer was one of relationship with the Father and communication with the Father. He spent time in prayer but he did not spent words in prayer.
He picks out one element of the prayer (which he taught his disciples) for practice and that is forgiveness. Forgiveness seems to be a pre-requisite when one enters into prayer.
In forgiving, we become a model to God himself. If we forgive others, then god will forgive us. Our forgiveness of our offenders is a pre-requisite for God’s forgiveness. So we become a model for God to forgive us. God will forgive us only if we forgive.