John Wesley on 1 Chronicles 26:16

Shallecheth - A gate of the court so called, as some think, because the ashes and filth of the temple were cast out on that side, which was the most convenient for that purpose, because that was a private quarter, the great ways to the temple lying on the other sides. Going up - By which causeway they went up towards the temple. Ward against ward - As one gate was over against another, the west against the east, and the north against the south, so one ward was over against another.