Altar (Bible)

Altars (Hebrew: מזבח‎‎, mizbe'ah, "a place of slaughter or sacrifice") in the Hebrew Bible were typically made of earth () or unwrought stone (). Altars were generally erected in conspicuous places (; ; ; ; ) The first altar recorded in the Hebrew Bible is that erected by Noah (). Altars were erected by Abraham (; ; ), by Isaac (), by Jacob (; ), and by Moses (Exodus 17:15, Adonai-nissi).

After the theophany on biblical Mount Sinai, in the Tabernacle–and afterwards in the Temple–only two altars are mentioned: the Altar of Burnt Offering, and the Altar of Incense.

The first altar was the Altar of Burnt Offering (mizbach ha'olah) (), also called the Brasen Altar (), the Outer Altar (mizbach hachitzona), the Earthen Altar (mizbach adamah), the Great Altar (mizbach hagedola) and the Table of the Lord, () This was the outdoor altar and stood in the Court of the Priests, between the Temple and the Court of Israel, and upon which the korbanot (animal and bird sacrifices) were offered. The blood of the sacrifices would be thrown against the base of the altar (; ), and portions of the sacrifices would be burned on top of it (precisely which portions would depend upon the type of sacrifice). Also consumed at the altar would be some of the meat offerings, and the drink offerings (libations of wine) were poured out here. All sacrifices had to be "seasoned with salt" (, )

There are three separate piles of wood burned atop the altar. The largest of these was where all the portions of the sacrifices were burned; the second fire provided the coals for the Altar of Incense within the sanctuary, and the third was the "perpetual fire" which constantly burned on the altar. Nothing was placed on it, and no coals were taken from it. It existed solely to fulfill the commandment that there be a perpetual fire, as the Torah states: "And a fire shall burn there on the altar constantly; it shall not be extinguished" (). There was no commandment regarding the type of wood to be used; however, the Rabbis forbade the use of olive wood and grape vine, as these would not burn well and needed to be conserved because of their commercial value to the people. Three particular types of wood were preferred: fig, walnut, and pine. These woods all burn well, and were therefore preferable. The choicest branches of fig were used for the second fire, the one from which coals were taken for the Altar of Incense. If all of the lamps of the menorah went out, they would have to be rekindled from the fire on the Altar of Burnt Offering.

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