Thus the “double portion,” so often associated with primogeniture (cf. Deut. 21:17; Isa. 61:7), is given to assist the older son in performing his responsibility of leadership for the welfare of the whole. In such a light, Israel will receive “the wealth of the nations” (Isa. 60:5, 11; 61:6) in the age to come.  - John P. Harrigan