Exodus 30:11-13

And the LORD spake unto Moses, saying, When thou takest the sum of the children of Israel after their number, then shall they give every man a ransom for his soul unto the LORD, when thou numberest them; that there be no plague among them, when {thou} numberest them. {their number: Heb. them that are to be numbered} This they shall give, every one that passeth among them that are numbered, half a shekel after the shekel of the sanctuary: (a shekel {is} twenty gerahs:) an half shekel {shall be} the offering of the LORD.