When you’re a child, forgiveness seems really simple: someone says sorry, you say you forgive them, and then you return to the jelly and ice cream.

But, as an adult, it’s a bit more complicated. How do I know that I’ve really forgiven someone? After all, it’s not just about saying “I forgive you”. Those are just words.

The late pastor Tim Keller suggested forgiveness involves three commitments:

Forgiveness is … a promise before God not to take revenge on a wrongdoer for his or her sin against you. Making that promise entails three practical commitments. You promise (1) not to constantly bring the sin up to the wrongdoer in order to browbeat and punish her, (2) not to constantly bring the sin up to other people in order to hurt the wrongdoer’s reputation and relationship with others, and (3) not to constantly bring the sin up to yourself—not to keep the anger hot, not to replay the video of it in order to cherish the feeling of nobility and virtue that comes from having been treated unjustly.

That’s powerful stuff. It’s not actually about “forgiving and forgetting“, the formula sometimes suggested. After all, it’s reasonable to protect yourself from someone you know typically behaves poorly in certain circumstances. But it is about not obsessing about that person’s past behaviour and not banging on about it.

To Keller’s list of commitments, I’d add a fourth: swerve away from schadenfreude – the feeling of pleasure around someone’s misfortune.

On the one hand, it’s good to feel positively about justice being served. Proverbs 21:15 tells us: “When justice is done, it brings joy to the righteous but terror to evildoers.” So it is perfectly reasonable to be pleased when the local muggers are brought to trial and given a sentence.

But Jesus teaches us something radical. We should also be praying for those muggers. This perhaps might involve asking for them to repent, find good role models and become respectable members of society. He’s what Jesus says (in Matthew 5):

You have heard that it was said, ‘Love your neighbour and hate your enemy.’

But I tell you, love your enemies and pray for those who persecute you, that you may be children of your Father in heaven. He causes his sun to rise on the evil and the good, and sends rain on the righteous and the unrighteous. If you love those who love you, what reward will you get? Are not even the tax collectors doing that?

So genuine forgiveness involves wanting a good outcome for the other person. After all, God himself came down from heaven in human form in an act of love towards those who had sinned against him.