John was born and raised as a Protestant, but grew up to do the worst thing he could do. That's right, he married a lovely Papist (Catholic) girl named Mary. Of course, to do so, he had to go to the vestry and take instruction and convert to Catholicism. John and Mary were happy newlyweds, but John did have some difficulty getting used to thinking of himself as a Catholic. He went to see Father Casey, the priest who married them, at the vestry, for some advice.

Father Casey hadn't seen this problem before, and was at a bit of a loss. He suggested that John simply repeat to himself, as often as possible, "You're a Catholic, not a Protestant." So John walked all the way home, muttering to himself, "You're a Catholic, not a Protestant; you're a Catholic, not a Protestant;you're a Catholic, not a Protestant; you're a Catholic, not a Protestant."

That Friday evening, Father Casey made his rounds to greet some of the Parish families. When he got to John and Mary's cottage, he thought he smelled something, and became curious, so he knocked on the door.

Mary greeted him fondly, invited him in, and returned to her chair and resumed her knitting. Before he took a seat, Father Casey asked, "Mary, where's John this fine evening?" Mary answered, "Oh, Father, he's in the kitchen, just over there. Go on through and say hello."

By this time, Father Casey was certain he was smelling a smell that no Catholic family's house should smell of on a Friday night (meat!). Sure enough, he went through to the kitchen and found John, standing over a steak on the pan on the stove. As he spooned the sauce over it, he was heard to repeat:

"You're a trout, not a steak; you're a trout, not a steak; you're a trout, not a steak."

* * *
My wife has done this kind of thing to me: We'll be sitting around a table with a bunch of other people, and several jokes have been told, and she will nudge me and say, out loud so everyone can hear: "Tell them the one that goes, 'You're a trout, not a steak.' " All I can do is facepalm at that point because she has already spoiled the joke. Nevertheless, people are staring at me waiting to hear it.