John Calvin Commentary Joshua 22:8

"and spake unto them, saying, Return with much wealth unto your tents, and with very much cattle, with silver, and with gold, and with brass, and with iron, and with very much raiment: divide the spoil of your enemies with your brethren." — Joshua 22:8 (ASV)

Return with much riches, etc. As it was formerly seen that the greater part of the two tribes were left in their territories beyond the Jordan, when the others passed over to carry on the war, it was fair that, as they had lived at ease with their families, or been only occupied with domestic concerns, they should be contented with their own livelihood and the produce of their own labor.

And they certainly could not, without dishonesty, have demanded that any part of the booty and spoil be distributed among them, since they had taken no share in all the toil and the danger. Joshua, however, does not insist on the strictly legal view, but exhorts the soldiers to deal liberally with their countrymen by sharing the prey with them.

Here, someone might inappropriately raise the question of whether or not the booty was common. For Joshua does not decide absolutely that it is their duty to do as he instructs; he admonishes them that, after they have been enriched by the divine blessing, it would betray a lack of proper feeling not to be liberal and kind towards their brothers, especially as it was not their fault that they did not take part in the same expedition. Moreover, when he tells them to divide, he does not demand an equal partition, such as is usual among partners and equals, but only to bestow something that may suffice to remove all cause of envy and hatred.