Social media is weird. IMO you did exactly the right thing. It is tough to figure out what to do next if he didn't respond, I think a lot of people are in the same boat with Facebook so please do not let it think it necessarily has anything to do with you. It could be as simple as he didn't have full access with a keyboard and a "like" was the only way to let you know he's out there. Or he could be shy about composing the next message. If you can get the pastor to arrange a meeting/introduction next maybe, let the pastor know you contacted him on Facebook.