I need help making it so a player keeps certain items upon death

I want to make a Bond enchantment where any items that have it on them act like keep inventory, however, I can't get it to work. Does anyone have any advice?

I cant figure out how to add screen shots, but what I'm doing is when an entity dies, I'm checking to see if its a player. If it is, then I check their inventory for items with the bond enchantment. This is where I'm stuck. How do I give the player their item back?