Todd apologized for what he did in the past.
What had he done to you?
He briefly dated my friend in the past.
It's good that your friend Todd is taking responsibility for his past actions.  Dating someone's friend can be an awkward situation, so I'm glad that he has made amends.
I'm going to punch him.
If he's apologizing for his mistake you should be kind enough forgive him. You could get in legal trouble for hitting him.