The Altar of Burnt Offering (Exodus 27:1-8).
The altar was to be covered with ‘brazen copper', probably copper alloyed with tin to make bronze. It was thus of inferior material compared with the gold and silver in the sanctuary, and served to demonstrate that through it earth met with heaven. It was the place where sin was dealt with. (There may also have been the practical purpose of it being more weatherproof and fireproof).
On that altar would be offered all the offerings and sacrifices of Israel which would result in forgiveness and mercy, pardon for sins, and the declaration of being made righteous (that is, as seen as without guilt) through the death of a substitute and representative offering, and would be the means by which they could offer themselves to God in dedication and thanksgiving, in praise and in worship, until the greater sacrifice came Who would offer Himself up once and for all (Hebrews 10:10).
We can analyse the passage as follows:
a The brazen alter was to be made of acacia wood overlaid with an alloy of bronze and copper. It was to have horns (upward projections) on its corners and be frousquare (Exodus 27:1-2).
b Its vessels to take away its ashes (literally ‘cleanse it from fat'), and its shovels and its basins and its fleshhooks and its firepans (or ‘receptacles'), all its accoutrements, were to be made with brazen copper (Exodus 27:3).
c They were to make a network grating of brass (copper), and on the net they were to make four brazen rings in its four corners.
c They were to put the network grating under the ledge (or ‘band') round the altar beneath, that the network might reach halfway up the altar (Exodus 27:4-5).
b They were to make staves for the altar, staves of acacia wood, and overlay them with brazen copper, and its staves were to be put into the rings, and the staves would be on the two sides of the altar for carrying it.
a They were to make it hollow with boards as shown to Moses in the Mount.
Note that in ‘a' how the brazen altar is to be constructed is described, and in the parallel it is to be made hollow with boards as Moses had been shown in the mount. In order for it to be used as an altar, earth or unhewn stone (Exodus 20:24-25) would have to be put within it on which to build the fire. In ‘b' we are informed about the instruments to be available for use at the altar, and in the parallel how it was to be carried. In ‘c' we have the description of the grating at the bottom of the altar and in the parallel the place where it was to be situated on the altar.
“And you shall make the altar of acacia wood, five cubits long and five cubits broad. The altar shall be foursquare, and its height shall be three cubits. And you shall make its horns on its four corners. Its horns shall be one piece with it. And you shall overlay it with brazen copper.”
The altar, which would be placed in the courtyard facing the Holy Place, was five by five by three cubits (220 x 220 x133 centimetres or 7 feet by 7 feet by 4:5 feet). It was made of acacia wood covered with brazen copper, (copper alloyed with tin. The exact type of metal is not certain and copper would be better suited and equally valuable) signifying God's strength and glory, but of a lesser value than the gold and silver within the sanctuary. But the brazen copper would be better placed to take the heat than gold. However, as much else is of brazen copper in this part of the Dwellingplace it is clear that it is intended to be an indication that the place was not as holy as the inner sanctuary. (And there would be a limit to the amount of gold available).
The setting of the altar outside the inner sanctuary would be necessary because of the continual smoke that would arise from the altar. But it was probably also in order to make it accessible to the people and to prevent any contact with sin from entering the inner sanctuary. It was an indication that in approaching God the very first step must be atonement.
Five was the number of covenant (compare the five words on each of the two tablets of the Law), and five by five, making a foursquare altar (emphasised as indicating its total compatability with its purpose), indicated the perfection of the covenant, and of this means of atoning for breaches in the covenant. The height of three cubits indicated completeness.
The four ‘horns' were upward projections at each of the four corners of the altar as found on the altars of other peoples discovered elsewhere. They may have been for tying the sacrifices to the altar (they were used for this - Psalms 118:27), or they may have indicated a pointing or reaching up to God. They may also have been intended to simulate the horns of an animal and thus be indicative of strength and power. As the altar of incense on which no sacrifices were offered also had these projections upwards the latter two interpretations are more probable as the main significance. Tying on the sacrifices was an added extra. This would suggest that the altar indicated heavenward movement and strength and power.
The foursquareness emphasis its perfection, but also that it falls short of the Most Holy Place which was a perfect cube. Compare also ‘the new Jerusalem' which represented the perfected people of God prepared as a bride for her Husband (Revelation 21:2; Revelation 21:16-17).
The blood of offerings and sacrifices was smeared on the horn with the finger (Exodus 29:12 - in the sanctifying of Aaron; Exodus 30:10 - in making atonement for the people once a year; Leviticus 4:18; Leviticus 4:25; Leviticus 4:30 - for the application of various sin offerings; Leviticus 8:15 - to purify it; Leviticus 9:9 - the sin offering for Aaron; Leviticus 16:18 - on the day of atonement for all the people; etc.), indicating that their significance was more than that of convenient projections for tying sacrifices on. This would serve to confirm the idea that they pointed upwards towards God.
The altar was seemingly a large hollow box, made hollow with planks (Exodus 27:8) and it is probable that unhewn stones and earth were used to fill the box preparatory to laying the wood for sacrifice (Exodus 20:24-25). These could be emptied out when it had to be carried, with new innards made whenever they became stationary at God's command. It was ideal for wilderness travel. It was the place where atonement was made (Leviticus 17:11). On it were offered the various offerings and sacrifices required by the Law.
The use of the definite article with altar has been overemphasised by some. Quite apart from the fact that the Hebrew definite article can simply mean ‘the one I am talking about' and nothing more, the making of a sanctuary would demand an altar of sacrifice and the article could thus mean simply ‘the altar necessary for the sanctuary'. It is not saying that there could not be an altar with a different significance as in Exodus 30:1.
“And you shall make its vessels to take away its ashes (literally ‘cleanse it from fat'), and its shovels and its basins and its fleshhooks and its firepans (or ‘receptacles'), all its accoutrements you will make of brazen copper.”
The different accoutrements for the altar were also made of brazen copper. The vessels for carrying away the ashes and remains of the fat, the shovels for shovelling them, the basins for catching the blood (Exodus 24:6), the fleshhooks for manoeuvring the sacrifices, and the firepans possibly for such tasks as carrying the ashes from the altar to the altar of incense (Leviticus 16:12).
“And you shall make for it a network grating of brass (copper), and on the net you will make four brazen rings in its four corners. And you will put it under the ledge (or ‘band') round the altar beneath, that the network might reach halfway up the altar.”
The network grating was in order to provide sufficient draught for the fire, and/or it may have contained the ashes that fell through from above, or it may have been a protection to prevent the actual altar being touched by the priests. The four rings were to take the poles used for carrying the altar. There was clearly a ledge (or band) round the altar midway between top and bottom, probably for the priests to stand on as they ministered at the altar. It could be made accessible by a mound of earth surrounding the altar. This would be why the priests wore special breeches. The altar was not to be approached by steps (20:26). The priests would have been of smaller stature than most of us and the altar would therefore be at head level. Others have argued that the ledge or band was only for decoration and strengthening.
Although overlaid with copper or brazen copper it will be quite apparent that this altar could not by itself contain a continually burning fire. It is clear therefore that some materials would have to be put within it on which the fire could be lit, which would absorb the heat. These materials were probably the earth or unhewn stones of Exodus 20:24-25. Thus did this permanent altar act in place of the altars built temporarily in different places where Yahweh recorded His name.
“And you will make staves for the altar, staves of acacia wood, and overlay them with brazen copper, and its staves will be put into the rings, and the staves will be on the two sides of the altar for carrying it.”
When on the move the altar would be borne by staves which went through the rings on each side of the altar.
“Hollow with boards you will make it. As it has been shown you in the Mount, so shall you make it.”
This confirms that the altar was hollow inside. The making of it in the exact pattern was necessary (compare Exodus 25:40) in order to prevent false impressions being given by the addition of things added to conform with other altars they had known. Beauty and splendour were incorporated but idolatrous associations must be abjured. The way to God had to be taken in the way that God laid down.