Dict: easton - Birthright

easton:

Birthright @

(1.) This word denotes the special privileges and advantages belonging to the first-born son among the Jews. He became the priest of the family. Thus Reuben was the first-born of the patriarchs, and so the priesthood of the tribes belonged to him. That honour was, however, transferred by God from Reuben to Levi kjv@Numbers:3:12-13 kjv@Numbers:8:18).

(2.) The first-born son had allotted to him also a double portion of the paternal inheritance kjv@Deuteronomy:21:15-17). Reuben was, because of his undutiful conduct, deprived of his birth-right kjv@Genesis:49:4; kjv@1Chronicles:5:1). Esau transferred his birth-right to Jacob kjv@Genesis:25:33).

(3.) The first-born inherited the judicial authority of his father, whatever it might be ( kjv@2Chronicals:21:3). By divine appointment, however, David excluded Adonijah in favour of Solomon.

(4.) The Jews attached a sacred importance to the rank of "first-born" and "first-begotten" as applied to the Messiah kjv@Romans:8:29; kjv@Colossians:1:18; kjv@Hebrews:1:4-6). As first-born he has an inheritance superior to his brethren, and is the alone true priest.