Numbers 2:2-3

2“Everyone of the children of Israel shall camp by his own standard, beside the emblems of his father’s house; they shall camp some distance from the tabernacle of meeting.

3On the east side, toward the rising of the sun, those of the standard of the forces with Judah shall camp according to their armies; and Nahshon the son of Amminadab shall be the leader of the children of Judah.”