ALTAR in the Bible Encyclopedia - ISBE
I. Classification of Hebrew Altars.
Before considering the Biblical texts attention must be drawn to the fact that these texts know of at least two kinds of altars which were so different in appearance that no contemporary could possibly confuse them. The first was an altar consisting of earth or unhewn stones. It had no fixed shape, but varied with the materials. It might consist of a rock (Jdg 13:19) or a single large stone (1 Sam 14:33-35) or again a number of stones (1 Ki 18:31 f). It could have no horns, nor it would be impossible to give the stone horns without hewing it, nor would a heap of earth lend itself to the formation of horns. It could have no regular pattern for the same reason. On the other hand we meet with a group of passages that refer to altars of quite a different type. We read of horns, of fixed measurements, of a particular pattern, of bronze as the material. To bring home the difference more rapidly illustrations of the two types are given side by side. The first figure represents a cairn altar such as was in use in some other ancient religions. The second is a conjectural restoration of Hebrew altars of burnt offering and incense of the second kind.
Importance of the Distinction:
Both these might be and were called altars, but it is so evident that this common designation could not have caused any eye-witness to confuse the two that in reading the Bible we must carefully examine each text in turn and see to which kind the author is referring. Endless confusion has been caused, even in our own time, by the failure to note this distinction, and the reader can hope to make sense of the Biblical laws and narratives only if he be very careful to picture to himself in every case the exact object to which his text refers. For the sake of clearness different terms will be adopted in this article to denote the two kinds of altars. The first will be termed "lay altars" since, as will be seen, the Law permitted any layman to offer certain sacrifices at an altar of earth or unhewn stone without the assistance of a priest, while the second while be styled "horned altars," owing to their possession of horns which, as already pointed out, could not exist in a lay altar that conformed with the provisions of the law...