Albert Barnes Commentary Exodus 27:1-8

"And thou shalt make the altar of acacia wood, five cubits long, and five cubits broad; the altar shall be foursquare: and the height thereof shall be three cubits. And thou shalt make the horns of it upon the four corners thereof; the horns thereof shall be of one piece with it: and thou shalt overlay it with brass. And thou shalt make its pots to take away its ashes, and its shovels, and its basins, and its flesh-hooks, and its firepans: all the vessels thereof thou shalt make of brass. And thou shalt make for it a grating of network of brass: and upon the net shalt thou make four brazen rings in the four corners thereof. And thou shalt put it under the ledge round the altar beneath, that the net may reach halfway up the altar. And thou shalt make staves for the altar, staves of acacia wood, and overlay them with brass. And the staves thereof shall be put into the rings, and the staves shall be upon the two sides of the altar, in bearing it. Hollow with planks shalt thou make it: as it hath been showed thee in the mount, so shall they make it." — Exodus 27:1-8 (ASV)

(Compare to Exodus 38:1-7.) The great altar that stood in the court immediately in front of the tabernacle was commonly called the altar of burnt offering, because on it were burned the whole burnt offerings and all those parts of the other animal sacrifices that were offered to the Lord. It was also called the brazen altar because it was covered with bronze, in distinction from the golden altar, or altar of incense (Exodus 39:38–39; Exodus 40:5–6).

His horns shall be of the same (Exodus 27:2) – These horns were projections pointing upward, in the form of either a small obelisk or an ox’s horn. They were to be actual parts of the altar, not merely added to it. On them the blood of the sin offering was smeared (Exodus 29:12; Leviticus 4:7; Leviticus 8:15; Leviticus 9:9; Leviticus 16:18). To take hold of them seems to have been regarded as an emphatic way of claiming the supposed right of sanctuary (Exodus 21:14 note; 1 Kings 1:50).

Pans (Exodus 27:3) – Rather, these were pots, as in Exodus 38:3 and 1 Kings 7:45. Regarding the use of these pots for disposing of the altar’s ashes, see Leviticus 1:16.

Basins – These were vessels used for receiving the blood of the victims and casting it on the altar (Leviticus 1:5; etc.).

Fleshhooks – These were used for adjusting the pieces of the victims on the altar (compare 1 Samuel 2:13).

Firepans – The same word is rendered “snuffdishes” (Exodus 25:38; Exodus 37:23) or “censers” (Leviticus 10:1; Leviticus 16:12; Numbers 4:14; Numbers 16:6; etc.). These utensils appear to have been shallow metal vessels used only to carry burning embers from the brazen altar to the altar of incense.

The compass of the altar (Exodus 27:5) – This was a shelf or projecting ledge, of convenient width, running around the altar halfway between the top and the base. It was supported all around its outer edge by a vertical, net-like bronze grating that rested on the ground.

Hollow with boards (Exodus 27:8) – This means slabs or planks, rather than boards. The word is the one used for the stone tables of the law (Exodus 24:12; Exodus 31:18), not the word applied to the boards of the tabernacle (Exodus 26:15).

The brazen altar was a hollow casing, formed of stout acacia planks covered with bronze plates, seven feet six inches in length and width, and four feet six inches in height. Jewish, as well as Christian, authorities have supposed that when it was set up for use, it was filled with earth or rough stones.

If we connect this suggestion with the ancient rule regarding the altar of earth and the altar of stone , the woodwork might, in fact, be regarded merely as the casing of the altar on which the victims were actually burned. The shelf around the sides (Exodus 27:5) was required as a platform for the priests to enable them to carry out their work conveniently on top of the altar. Hence, it is said of Aaron that he came down from the altar (Leviticus 9:22).

According to rabbinical tradition, there was a slope of earth at the south side, banked up for the priest to ascend to the platform .