Joshua 22:12
And when the children of Israel heard of it, the whole congregation of the children of Israel gathered themselves together at Shiloh, to go up to war against them. And when the children of Israel heard of it, the whole congregation of the children of Israel gathered themselves together at Shiloh, to go up to war against them.
The gathering at Shiloh was the whole congregation of Israel assembling to go to war against Gad and Reuben and the half tribe of Manasseh east of the Jordan. Those two and a half tribes had received their inheritance east of the Jordan in the grazing lands of Gilead and Bashan. They had pledged armed men to fight with their brethren in Canaan until the conquest was finished, had faithfully fought for years with forty thousand prepared for war, and had then returned with much riches, cattle, silver, gold, brass, iron and clothing to be shared with those who had remained with the families and flocks.
They were then to dwell at a distance from the sanctuary, where isolated life near heathen tribes brought strong temptation to fall into heathen customs, which caused anxious foreboding over their departure. The immediate trigger for the gathering was the report that the eastern tribes had erected a large altar near the Jordan. The builders were actuated by worthy motives and meant the altar only as a witness that, though separated by the river, they were of the same faith and entitled to equal privileges in the tabernacle at Shiloh.
The western congregation supposed the altar was designed to take the place of the tabernacle, suspected the eastern tribes of turning from God, and feared it would lead the people away from the true faith and bring the wrath of God upon the whole nation. Their response was excited, indignant, and determined to make war at once. Their zeal to protect true worship and their sincere fear of division and religious defection were prompted in part by the earlier failure to discover Achan's sin.
In that zeal they gathered for war before learning the full facts, condemning their brethren on suspicion and going too far, so that a misunderstanding nearly brought disastrous consequences. Their rush to war was checked when men of caution proposed first sending Phinehas the high priest and ten princes to require an explanation, showing that they should first have courteously asked about the facts. The episode teaches that people who are honestly serving God can be wrongly suspected and rebuked, and that meekness and forbearance rather than anger or retaliation can avert great harm.