Bearing with one another, and forgiving each other, if any man has a complaint against any; even as Christ forgave you, so you also do.
Paul knows how easily forgiveness turns into a calculation, so he does something quietly clever. He moves the standard. Not forgive them because they deserve it, but as Christ forgave you.
The moment he does that, the argument changes shape. The question is no longer whether the other person has earned it. The question is whether you earned what you were given, and you already know the answer to that.
He also describes forgiving someone who has a complaint against any, which is worth noting. Both parties may believe they are the wronged one. Paul does not ask you to settle who is right. He asks you to forgive, because you have already been on the receiving end of it.
And notice the phrase he begins with: bearing with one another. Forgiveness here is not a single event. It is a habit, practised on repeat, often for the same person.