DEU 33:21

21 They chose the best part of the land for themselves; [a large share of the land], a share that should be given to a leader was allotted to them. When the leaders of the tribes of Israel [gathered together], they decided that the tribe of Gad should have a large share of the land. The tribe of Gad obeyed the commands of Yahweh and the things that he decided that they should do.