Exodus 30:13-17

This is what everyone who is counted shall give: half a shekel according to the shekel of the sanctuary (the shekel is twenty gerahs), half a shekel as a contribution to the Lord.

Everyone who is counted, from twenty years old and over, shall give the contribution to the Lord.

The rich shall not pay more, and the poor shall not pay less, than the half shekel, when you give the contribution to the Lord to make atonement for yourselves.

And you shall take the atonement money from the sons of Israel and give it for the service of the tent of meeting, so that it may be a memorial for the sons of Israel before the Lord, to make atonement for yourselves.”

Then the Lord spoke to Moses, saying,