Heaping Coals

God alone has the perfect knowledge of the conditions that bring about people's evil actions, the motives that drive those actions, and the far-reaching impact of those actions upon others. This perfect knowledge is necessary for God to act with perfect justice. We, on the other hand, do not know these things and so we leave judgement and the execution of justice to God. And yet we have a part in his justice when with goodness we heap coals upon the heads of our enemies.