It’s hard to find anything to learn or take on board personally from some of these minor prophets.
This verse (and the few following it) seems to be a pretty universal principle, though: you should not rejoice in the misfortunes – or even the just punishments – of others.
It goes on to say, “As you have done it will be done to you” (v15). This covers both the things Edom actively did, and the things it failed to do, its attitudes as well as its actions. We are as responsible for the attitudes of our hearts as for the injustices we commit or the acts of mercy we fail to do. What a challenging thought!