Redeem them when they are one month old. The redemption price is five pieces of silver (as measured by the weight of the sanctuary shekel, which equals twenty gerahs).
Each person who is counted must give a small piece of silver as a sacred offering to the Lord. (This payment is half a shekel, based on the sanctuary shekel, which equals twenty gerahs.)
The people brought special offerings of gold totaling 2,193 pounds, as measured by the weight of the sanctuary shekel. This gold was used throughout the Tabernacle.
“The firstborn of every mother, whether human or animal, that is offered to the Lord will be yours. But you must always redeem your firstborn sons and the firstborn of ceremonially unclean animals.
“However, you may not redeem the firstborn of cattle, sheep, or goats. They are holy and have been set apart for the Lord. Sprinkle their blood on the altar, and burn their fat as a special gift, a pleasing aroma to the Lord.