Deuteronomy 21:16

21:16 then it shall be, in the day that he causes his sons to inherit that which he has, that he may not make the son of the beloved the firstborn before the son of the hated, who is the firstborn:
-World English Bible

Other Translation

21:16 Then it shall be, when he maketh his sons to inherit [that] which he hath, [that] he may not make the son of the beloved firstborn before the son of the hated, [which is indeed] the firstborn:
-King James Version