Numbers 12:11 and he said to Moses, ‘Please, my lord, I ask you not to hold against us the sin we have so foolishly committed.
When Aaron and Miriam talked badly about Moses, God heard them and confronted them with the truth.
Aaron had to admit to what he had done and upon seeing what happened to Miriam, begged Moses to forgive them for talking bad about him.
Moses did the right thing and forgave them, calling on God to heal Miriam.
This is what Jesus teaches us too – when we sin against someone, confront them and ask for forgiveness, When someone begs for forgiveness, forgive them – asking God for help!