"Can't Tell Ya" joke

A man worked at a gas station out in the middle of nowhere. One day when he was driving home from work, he ran out of gas (how ironic). So the man walks and walks and eventually he comes upon a monastery.
He asks a monk at the monastery, "Can I stay here over night? My car ran out of gas."
The monk replies, "You may; but you musn't come out of your room between the hours of 12 midnight and 6 am."
The man replies, "That's fine with me." The monk takes him to his room, and the man falls asleep.
About 12 midnight the man is roused from his sleep by a horrible groaning noise that was coming from the basement. He gets out of his bed to see what it is, but remembers the monk saying that he couldn't leave his room between 12 and 6 am. The groaning keeps the man awake all night long until it finally stops at 6.
The next morning the man asks the monk from yesterday, "What was that racket coming from the basement?"
"I can't tell you. You're not a monk," the monk replies.
So the man gets some gas from the monk, fuels up his car and drives home. For a year that groaning noise haunts him. The man decides to become a monk so he can find out what it was.
The man goes to monk school, and afterwards goes to the monastery that he arrived at a year ago.
He asks a monk there, "Can I stay here for the night?"
The monk replies, "Yes, but do not come out of your room between the hours of 12 midnight and 6 am."
"Why not?" the man asks.
"I can't tell you. You're not a monk," the monk replies.
"Yes, I am," the man says.
"Well, just don't come out," the monk says.
That night the man is awakened by the groaning noise. The man thinks, 'I'm a monk, so I can go and see what it is. The man walks down to the first floor and opens the door to the basement.
It had been bugging him for sooo long what the groaning noise was in the basement. It had haunted his dreams, scared him in the day, and he had gone through monk school and everything JUST to see what the groaning noise was in the basement. It was a strange noise, and he was finally able to see what it was, after a whole 365 days. He was just so excited to know what it was, so he wouldn't be haunted anymore. So he went down to the basement, sighed, and slowly creaked the door open to see what he had been wanting to see for the longest time.
Do you know what the man saw in the basement? I can't tell you. You're not a monk.