Why lui and not le?

Question

Je lui pardonnerai que vous soyez d'accord ou pas. I am probably being very stupid as this seems elementary. But I have forgotten the reason.

Céline Pickard · Accepted Answer

Bonjour Chris,
There are no stupid questions on this site! It's a perfectly valid question too!
Here, in this sentence, the expression is "pardonner [quelque chose] à [quelqu'un]". Therefore, the object pronoun will be indirect due to the preposition à. Remember that "le" as an object pronoun refers to a direct object while "lui" refers to an indirect object.
Je prépare le gâteau -> Je le prépare
Je pardonne à Luc son indiscrétion -> Je lui pardonne son indiscrétion
I hope this is helpful.
Bonne journée !