God spoke to Moses:
"When you take a head count of the Israelites to keep track of them, all must pay an atonement-tax to God for their life at the time of being registered so that nothing bad will happen because of the registration.
Everyone who gets counted is to give a half-shekel (using the standard Sanctuary shekel of a fifth of an ounce to the shekel) - a half-shekel offering to God.
Everyone counted, age twenty and up, is to make the offering to God.
The rich are not to pay more nor the poor less than the half-shekel offering to God, the atonement-tax for your lives.
Take the atonement-tax money from the Israelites and put it to the maintenance of the Tent of Meeting. It will be a memorial fund for the Israelites in honor of God, making atonement for your lives." The Washbasin