And on the other side of Jordan, of the Reubenites, and the Gadites, and of the half tribe of Manasseh, with all manner of instruments of war for the battle, an hundred and twenty thousand. (1 Chronicles 12:37)
This large total for the two and a half tribes east of the Jordan is indeed remarkable. That David should have so large a number of men in his army from the eastern tribes and have only 6,800 men from his own tribe of Judah may find explanation in the observation that David was already king over Judah and the 6,800 probably represent only the elements that had been disloyal hitherto.