Numbers 1:6

from twenty years old and upward, all who are able to go out to war in Israel. You and Aaron shall count them by their divisions.

With you there shall be a man of every tribe, each one head of his fathers’ house.

These are the names of the men who shall stand with you:

Of Reuben: Elizur the son of Shedeur.

Of Judah: Nahshon the son of Amminadab.

Of Issachar: Nethanel the son of Zuar.

Of Zebulun: Eliab the son of Helon.