Charles Ellicott Commentary Joshua 22:26

"Therefore we said, Let us now prepare to build us an altar, not for burnt-offering, nor for sacrifice:" — Joshua 22:26 (ASV)

An altar. —Rather, the altar. It was not an altar (Joshua 22:23), but the altar, that is, the pattern or copy of the altar of Jehovah, to prove that the two and a half tribes had the same right to approach Him as all the rest.