Joshua 22:11
And the children of Israel heard say, Behold, the children of Reuben and the children of Gad and the half tribe of Manasseh have built an altar over against the land of Canaan, in the borders of Jordan, at the passage of the children of Israel.
Cross-reference
Leviticus 17:8
Historical context
Leviticus 17:8 commands all sacrifices be brought to the tabernacle — this law explains why the tribes' altar causes concern of rebellion.
Leviticus 17:9
Historical context
Leviticus 17:9 repeats the penalty for not bringing sacrifices to the tabernacle — reinforcing the law the altar appears to violate.
Deuteronomy 12:5–7
Historical context
Deuteronomy 12:5-7 mandates worship only at the place God chooses — the altar across the Jordan conflicts with this centralization law.
Deuteronomy 13:12–14
Historical context
In Deuteronomy 13:12-14, the law commands diligent inquiry when a report of apostasy arises — this is the legal background for Israel's reaction here.