At the end of each tax year the Tax Office sent an inspector to audit the 
books of a synagogue.

While he was checking the books he turned to the Rabbi and said, 'I notice 
you buy a lot of candles. What do you do with the candle drippings?'

'Good question,' noted the Rabbi. 'We save them up and send them back to the 
candle makers, and every now and then they send us a free box of candles.'

'Oh,' replied the auditor, somewhat disappointed that his unusual question 
had a practical answer. But on he went, in his obnoxious way.

'What about all these matzo purchases? What do you do with the crumbs?'

(Matzo: A very thin brittle biscuit of unleavened bread)

'Ah, yes,' replied the Rabbi, realising that the inspector was trying to 
trap him with an unanswerable question. 'We collect them and send them back 
to the manufacturers, and every now and then they send a free box of matzo 
balls.'

'I see,' replied the auditor, thinking hard about how he could fluster the 
know-it-all Rabbi. 'Well, Rabbi,' he went on, 'what do you do with all the 
leftover foreskins from the circumcisions you perform?'

'Here, too, we do not waste,' answered the Rabbi. 'What we do is save up all 
the foreskins and send them to the Tax Office, and about once a year they 
send us a complete dick.'