not tell him, let him find out for himself and then claim you have no idea what happened?
just tell him "Hey, this happened, sorry"?
tell him "Hey, this happened, sorry" and offer to buy him a new one?
just buy him a new one and replace it before he notices?
On an unrelated note, do you partake in religious activities on Sundays? What might they be?
Do you wanna rock and roll all night?