What is more important: mercy or justice?

[glatt]

Justice, tempered with Mercy.

I'm thinking of my own children here. You need to teach them right from wrong. They need to know that actions have consequences. But you don't want to be a hard ass who breaks their spirit. So lay out the rules. Let them know what's expected. Be consistent. Dole out the reasonable and proportionate punishments. And every once in a while show some sympathy for their situation because they really are trying their best and sometimes make mistakes.