Deuteronomy 33:21
And he provided the first part for himself, because there, in a portion of the lawgiver, was he seated; and he came with the heads of the people, he executed the justice of the Lord, and his judgments with Israel.
Cross-references
Numbers 32:1-6 records the request of Gad and Reuben for the east Jordan land — the 'best part' chosen here.
Numbers 32:16-42 details the pledge to fight and the inheritance — the commander's portion referenced in this blessing.
Numbers 32:21 states the condition 'go armed before the Lord' — echoing the blessing's 'came with the heads of the people'.
Numbers 32:33 explicitly records Moses giving the land to Gad — the 'best part' chosen.
Joshua 1:14 commands the Gadites to cross over armed — fulfilling Gad's role 'with the heads of the people' from this blessing.
Joshua 4:12 describes the Gadites crossing armed — fulfilling the blessing's description of their participation.
Joshua 4:13 shows Gad's armed men crossing the Jordan, fulfilling Moses' blessing that Gad would lead the people in battle.
Joshua 22:4 dismisses the eastern tribes after conquest — completing their duty mentioned in this blessing.
Genesis 49:19 is Jacob's blessing on Gad; both are prophetic blessings on the same tribe, with different imagery.