Genesis 17:11-13

Amplified Bible

¹¹ And you shall be circumcised in the flesh of your foreskins, and it shall be the sign (symbol, memorial) of the covenant between Me and you. ¹² Every male among you who is eight days old shall be circumcised throughout your generations, [including] a servant whether born in the house or one who is purchased with [your] money from any foreigner, who is not of your descendants. ¹³ A servant who is born in your house or one who is purchased with your money must be circumcised; and [the sign of] My covenant shall be in your flesh for an everlasting covenant.