Cross reference
Deuteronomy 21:17
17 but he shall acknowledge the first-born, the son of the hated, by giving him a double portion of all that he hath; for he is the beginning of his strength; the right of the first-born is his.
Genesis 49:3
3 Reuben, thou art my first-born, my might, and the beginning of my strength; The pre-eminence of dignity, and the pre-eminence of power.
Genesis 25:31-34
31 And Jacob said, Sell me first thy birthright.
32 And Esau said, Behold, I am about to die. And what profit shall the birthright do to me?
33 And Jacob said, Swear to me first. And he sware unto him. And he sold his birthright unto Jacob.
34 And Jacob gave Esau bread and pottage of lentils. And he did eat and drink, and rose up, and went his way. So Esau despised his birthright.
Genesis 25:5-6
5 And Abraham gave all that he had unto Isaac.
6 But unto the sons of the concubines, that Abraham had, Abraham gave gifts. And he sent them away from Isaac his son, while he yet lived, eastward, unto the east country.
1 Chronicles 5:1-2
1 And the sons of Reuben the first-born of Israel (for he was the first-born; but, forasmuch as he defiled his father's couch, his birthright was given unto the sons of Joseph the son of Israel; and the genealogy is not to be reckoned after the birthright.
2 For Judah prevailed above his brethren, and of him came the prince; but the birthright was Joseph's:)
Psalms 105:36
36 He smote also all the first-born in their land, The chief of all their strength.