John Wesley on Ezekiel 43:13

The altar - Of burnt - offerings. And an hand - breath - The sacred cubit, three inches longer than the common cubit. The bottom - The ledge or settle, fastened to the altar on all sides at the bottom, shall be a cubit in height. The breadth - From the edge of this bench on the outside to the edge where it joined the body of the altar, a cubit, and this the breadth, twenty one inches, broad enough for the priests to walk on. Border - A ledge going round on all the squares. The edge - On the outer edge of this settle a span high. The back - As the back bears burdens, so this was to bear the weight of the whole altar.