The act of posting ones religious beliefs on Facebook on a daily basis when in reality the don't follow the advice they are giving to everyone else. Usually ends up on someones blocked list, or unfriended.
Friend 1- Dude why's your mom always talking about the bible on Facebook? Does she not know that no one cares?
Friend 2- Idk shes such a Facebook Preacher because all she really does is sit around and smoke all day and watch Jeopardy and Wheel of Fortune.
Friend1- Oh OK.