"And of Gad he said: 'Blessed is He Who grants expanse to Gad; he dwells like a lion, tearing the arm [of his prey, together] with the head. He saw the first portion for himself, because there, the portion of the lawgiver is hidden. And he came at the head of the people; he did what is righteous for the L-rd, and what is lawful with Yisra'el'" [Devarim 33: 20-21].
"Gad’s territory extended far eastward" — [Sifrei 33: 20].
"Anyone slain by B'nei Gad could be readily identified: they used to cut off the head together with the arm in one blow" — [Jonathan Ben Uziel].
"The Gadites marched before the armed forces in the conquest of the Land, because the Gadites were powerful, and so it is said [of them], 'Pass over, armed, before your brothers'" [Devarim 3: 18].