Deuteronomy 21:17
But he shall acknowledge the son of the hated as the first-born by giving him a double portion of all that he has. For he is the beginning of his strength. The right of the first-born is his.
Genesis 49:3
Reuben, you are my first-born, my might, and the beginning of my strength, the excellency of dignity and the excellency of power.
Genesis 25:31-34
And Jacob said, Sell me your birthright today.
Genesis 25:5-6
And Abraham gave all that he had to Isaac.
1 Chronicles 5:1-2
And the sons of Reuben, the first-born of Israel (for he was the first-born; but since he defiled his father's bed, his birthright was given to the sons of Joseph the son of Israel, and the genealogy is not to be counted according to the birthright;
Psalm 105:36
He also struck all the first-born in their land, the chief of all their strength.