At the first session of a conversion class...
At the first session of a conversion class the minister conducting the class asked, "What must we do before we can expect forgiveness from sin?" After a long silence, one of the men in attendance raised his hand and said: "Sin?"

After surgery
As the lawyer slowly came out of the anesthesia after surgery, he said, "Why are all the blinds drawn, doctor?"

"There's a big fire across the street," the doctor replied. "We didn't want you to think the operation was a failure."