The altar of burnt offering was basically a hollow square box made of wood overlaid with copper or bronze. At its four corners were four horn-like projections. Four copper or bronze rings, with two on one side of the altar and two on the opposite side, were used to insert the wooden poles overlaid with copper or bronze. These poles functioned as the means for carrying the altar. A grating consisting of a copper or bronze network was positioned inside the hollow boxlike altar, which measured five cubits (7.5 feet [c. 2.3 meters]) in length, five cubits in width, and 3 cubits (4.5 feet [c 1.4 meters]) in height. Whereas Moses had been shown a pattern that provided him with the details needed to construct the altar, readers of the account now are much more limited in understanding what was recorded about the altar and how the officiating priests would have carried out their functions at the altar. (27:1-8; see the Notes section.)
The altar of burnt offering had its designated location in the courtyard around the tabernacle. This courtyard was surrounded by 5-cubit (7.5-foot [c. 2.3-meter]) high linen hangings that measured 100 cubits (150 feet [c. 45.7 meters]) on the south and north sides, and 50 cubits (75 feet [c. 23 meters]) on the west side. The 50-cubit east side had an entrance that measured 20 cubits (30 feet [c. 9 meters]) across and that had an entrance screen of fine twisted linen, seemingly embroidered with blue (or blueish purple), purple (or reddish purple), and crimson yarns. Copper or bronze pillars supported the linen hangings on the four sides of the courtyard. The hangings were suspended from silver hooks and bands (rings or hoops) attached to the pillars. Both on the north and south sides, the 20 pillars were secured in copper or bronze bases, and the 10 pillars on the west side had ten corresponding copper or bronze bases. The arrangement on the east side required three pillars for the 15-cubit (22.5-foot [c. 6.9-meter] hangings on each side of the entrance, and four pillars for supporting the 20-cubit (30-foot [c. 9-meter] entrance screen. (27:9-18)
All utensils used in the courtyard were made from copper or bronze, as were all the pegs needed for attaching the tabernacle outer covering and the courtyard hangings to the ground. (27:3, 19)
For keeping the lamps on the lampstand burning, the Israelites were to contribute pure oil from beaten olives. Aaron and his sons were the ones to set up the lampstand with its lamps in the Holy, or on the east side of the curtain that separated the Holy from the Most Holy. The lamps were to be kept burning before YHWH from evening to morning, requiring that the Israelites provide the needed olive oil throughout their generations. (27:20, 21)
There is archaeological evidence for a cubit of approximately 17.5 inches (44.5 centimeters), but 18 inches (c. 46 centimeters) for a cubit (as commonly found in many reference works) is used in Werner Bible Commentary because it reduces the number of fractions involved when calculating cubit measurements in inches, feet, centimeters, and meters.
The wood is commonly considered to have been acacia wood because of its suitability for construction purposes and its availability on the Sinai Peninsula.
Verse 4 indicates that copper or bronze rings were to be attached at the four corners of the grating. This appears to have been a removable grating. The designated place for the grating was to be “halfway down the altar” below the altar ledge. (Verse 5) According to the Septuagint, the rings were to be placed under the grating of the altar, and the grating itself was to be positioned “unto the middle of the altar.”
In the descriptions, the main references are to dimensions and materials. This information is readily conveyed by means of the spoken or written word. What was visually revealed is not included in the account, and this makes it impossible to represent the tabernacle, the courtyard hangings, and the utensils and furnishings exactly as they existed many centuries ago. The absence of any detailed description of the cherubs may also have prevented the making of images for use in idolatrous practices.