Numbers 18:16

All the gold that was used for the work, in all the work of the sanctuary, even the gold of the wave offering, was 29 talents and 730 shekels, according to the shekel of the sanctuary.

‘If your valuation is of the male from twenty years even to sixty years old, then your valuation shall be fifty shekels of silver, according to the shekel of the sanctuary.

‘But if they are from a month even up to five years old, then your valuation shall be five shekels of silver for the male, and for the female your valuation shall be three shekels of silver.

‘Every valuation of yours, moreover, shall be according to the shekel of the sanctuary. The shekel shall be twenty gerahs.

“For the redemption price of the 273 of the firstborn of the sons of Israel who are in excess beyond the Levites,

you shall take five shekels apiece, per head; you shall take them in terms of the shekel of the sanctuary (the shekel is twenty gerahs),

Do you not know that those who perform sacred services eat the food of the temple, and those who attend regularly to the altar have their share from the altar?