A saying to show your astonishment, or to accent what you are saying. It can also be a totally random response to anything anyone says. It can also be to show disapproval.
A statement similar to Jesus-Fucking-Christ that is often used in a situation of utter disbelief, shock or frustration. It is arguably blasphemy as well. Can be announced slowly and clearly to express disgust and hopelessness, or loud and fast to alert someone of an imminent disaster that will most likely end in catastrophe.
Also might be a sign of Tourette syndrome.
Jesus-Titty-Ass-Mother-Fucking-Christ! I almostdied!