en_tn/jos/04/12.md

The tribe of Reuben, the tribe of Gad, and the half tribe of Manasseh passed before the people of Israel formed up as an army

These were the soldiers of the 3 tribes that were fulfilling their obligation to lead the Israelites into battle for settling on the East side of the Jordan River. (See: rc://en/ta/man/jit/figs-explicit)