“And those that are to be redeemed from a month old shalt thou redeem, according to thine estimation, for the money of five shekels, after the shekel of the sanctuary, which is twenty gerahs.”
King James Version (KJV)
18:16 Those that are to be redeemed - Namely, of men only, not of unclean beasts, as is manifest from the time and price of redemption here mentioned, both which agree to men; the time, #Num 18:16|, the price, #Num 3:46|,47, but neither agree to unclean beasts, which were to be redeemed with a sheep, #Exo 13:13|, and that after it was eight days old.