I have decided that I'm not going to reconnect with an old acquaintance after his father passed
That's unfortunate. Are you two still on friendly terms?
No, he ridiculed me for no reason to my face in the past.
It's not wrong to avoid someone from the past, even if their family members die, if that person was abusive to you. It's probably healthier for your mental state to avoid anyone who acts that way towards you, but you should still forgive him so that you have closure.
No, I won't forgive him. He deserves this happening to him.
Wouldn't you want to have a clean conscience, though? While it's fine to no longer be friends, are you fine with keeping bitter feelings towards him that may be painful to you? I think it's wiser to attempt to contact them once last time, and have some appropriate closure so you can move on properly.