Exodus 30:13-15

Amplified Bible

¹³ This is what everyone who is counted shall give [as he joins those already counted]: a half shekel, according to the sanctuary shekel (the shekel is twenty gerahs); a half shekel as a contribution to the Lord. ¹⁴ Everyone who is counted, from twenty years old and over, [as he joins those already counted], shall give this contribution to the Lord.^{(A) 15} The rich shall not give more and the poor shall not give less than half a shekel, when you give this contribution to the Lord to make atonement for yourselves.