I don't know what you mean by "block". Are they friends? People often have their pages set up for their immediate friends and families. That's not about you, it is just what they are doing in their own lives. The only people I know who befriend anyone who asks are those playing games where it matters how many "friends" you have. Just because you go to the same church as these people, if you are not good friends there, I would not worry about not being friends on facebook.