An old Jewish joke.

[Dave in Tenn]

A rabbi, a Cantor, and the synagogue's janitor are preparing the synagogue for Sabbath services. 

While the Janitor cleans, the Rabbi prostrates himself and prays, "Oh Lord, You are so Great and I am nothing beside you." then returns to his preparations.

The Janitor continues to clean and tidy up, as the Cantor prostrates himself and repeats the Rabbi's prayer, "Oh Lord, You are Great, and I am nothing beside you."  Then he too returns to his preparations.

Finally the janitor finished his work, and before he leaves prostrates himself and prays, "Oh Lord, You are so Great.  I am nothing beside you."

The Cantor, seeing this, elbows the Rabbi and says, "Hmmph.  Look who things he's nothing."

[Dennis Vogel]

Good one.