Genesis 49:3

“Reuben, you are my firstborn;

My might and ^athe beginning of my vigor,

¹Preeminent in dignity and ¹preeminent in strength.

Deuteronomy 21:17

17 But he shall recognize the firstborn, the son of the ¹unloved, by giving him a double portion of all that ²he has, for he is the ^afirst of his vigor; ^bthe legal judgment for the firstborn belongs to him.