Numbers 36:7

So shall not the inheritance of the children of Israel remove from tribe to tribe: for every one of the children of Israel shall keep himself to the inheritance of the tribe of his fathers.

Cross-references

Numbers 36:9 repeats the same prohibition against inheritance passing between tribes, reinforcing the command.

1 Kings 21:3 shows Naboth refusing to sell his ancestral inheritance, upholding the principle that tribal land must stay within the tribe.