וְהָיָ֗ה בְּיוֹם֙ הַנְחִיל֣וֹ אֶת־בָּנָ֔יו אֵ֥ת אֲשֶׁר־יִהְיֶ֖ה ל֑וֹ לֹ֣א יוּכַ֗ל לְבַכֵּר֙ אֶת־בֶּן־הָ֣אֲהוּבָ֔ה עַל־פְּנֵ֥י בֶן־הַשְּׂנוּאָ֖ה הַבְּכֹֽר׃
then it shall be, in the day that he causeth his sons to inherit that which he hath, that he may not make the son of the beloved the first-born before the son of the hated, who is the first-born;
Targum Jonathan on Deuteronomy
it shall be in the day that he deviseth to his sons the inheritance of the wealth that may be his, he shall not be allowed to give the birthright portion to the son of the beloved, over the head of the son of the hated wife, to whom the birthright belongs;