Bearing with one another and, if one has a complaint against another, forgiving each other; as the Lord has forgiven you, so you also must forgive.
Bearing with people is hard enough. Forgiving them for something real, something that actually cost you — that's a different level. This verse doesn't pretend otherwise. It says "if one has a complaint against another," like it's assuming you will have one, sooner or later, from someone close to you.
What's striking is the measuring stick: forgive as the Lord forgave you. Not as much as feels fair. Not once you've cooled off enough. As you were forgiven — which, if you think about it, is a strange thing to ask of someone who isn't sure they believe in a God who forgives anything.
You don't need a tidy theology to notice the logic here, though: something in us that's been forgiven generously finds it easier to forgive generously. Maybe that's worth testing out before you decide whether the God behind it is real.
If you're curious what it would actually feel like to be forgiven that completely, that's a door worth knocking on.
A short video on this is coming soon — for now, read on.