MANY reasons can come to mind to answer that question. One is that Christ himself said so. When asked by Peter how many times one should forgive, he stretched to practically infinite times the suggestion of Peter of 7 times to 70 times 7.
On another occasion, Christ also said that we need to forgive others if we want to be forgiven ourselves. “Forgive and you shall be forgiven,” he said (Lk 6,37) He reiterated this injunction when he said: “For if you will forgive men their offences, your heavenly Father will forgive you also your offences. But if you do not forgive men, neither will your Father forgive you your offences.” (Mt 6,14-15)
It’s clear therefore that we can only be forgiven if we also forgive others. This injunction is meant for everyone, and not only for a few whom we may consider to be religiously inclined.
That’s also why he easily forgave the woman caught in adultery. And to those whom he cured of their illnesses, it was actually the forgiveness of their sins that he was more interested in.
To top it all, Christ allowed himself to die on the cross as a way to forgive all of our sins, and to convert our sins through his resurrection as a way to our own redemption. What he did for us he also expects, nay, commands that we also do for everybody else.
If Christ can offer forgiveness to those who crucified him—and there can be no worse evil than killing Christ who is God—why do we find it hard to offer forgiveness to others?
It is presumed that all of us sin one way or another. That’s why St. John said: “If we say that we have no sin, we deceive ourselves, and the truth is not in us.” (1 Jn 1,8) I am sure that our personal experiences can bear that out easily.
No matter how saintly we try ourselves to be, sin always manages to come in because of our wounded humanity and the many temptations within and around us. As St. John said, we have to contend with three main enemies: our own wounded flesh, the devil and the world corrupted by our own sin.
But the most important reason why we should always forgive is, I believe, the fact that forgiving others likens us with God, with Christ, who is the pattern of our humanity and the savior of our damaged humanity. Forgiving is the ultimate act of love which is the very essence of God and which is also intended for us since we are supposed to be God’s image and likeness.
Thus, we have to learn to be forgiving always of others, no matter how undeserving we feel they are of forgiveness. That’s how God forgave us. He took the initiative. He offered forgiveness and continues to do so if only to bring us back to him.
The awareness of this truth should also help us to develop the attitude to forgive one another as quickly as possible, since that is the only way we can learn to love. When we find it hard to forgive others, it is a clear sign that we are full of ourselves, are self-righteous, proud and vain.
We have to continually check on our attitude towards others because today’s dominant culture is filled precisely by the viruses of self-righteousness, that feeling that we are superior to others, etc. We have to do constant battle against that culture that undermines our duty to be always forgiving.