You reminded me of a swear that works better in croatin, but here it goes:
F*ck soup made from nails Jesus Christ was crucified with
Jesus H. Christ --> Jesus Fucking Christ
Jesus --> Fuck that Jesus dude.
BTW - this is a losing battle. The speech center that provides the wellspring of spontaneous epithets is not the same as the cognitive speech center. Read Steven Pinker instead of wishing in one hand and shitting in the other.
Just in respondse to the title:
I think that blaspheming against a religion is hardly advancing its cause. Almost any Christian would object to using "Jesus Christ" and "shit" in the same contexts. Blasphemy is, after all, expressly forbidden to its constituents. It seems almost like a kind of protest against religion, showing that we don't fear its power.
I've found its also fun to change it up and swear with different religions. It's easy to get around taboos that way.
I don't remember if it was from Dennet or Dawkins but an alternative for :
That was Dennet describing how glad he was he survived some medical emergency, at the 2007 AAI conference. Now whether that's where it originated is another question.