If you block a user, you cant see THEIR posts. It says "you cant see this persons post cuz you havd them on ignore". Presumably you block them because what they write upsets you. Therefore they find out that you have blocked them when they try to respond to your thread or your post on someone elses thread. It says, this person has you on ignore, you cant reply.

You can howevrr stillnhug or thank them.