Biblical References
Within the Torah, the showbread is mentioned exclusively by the Priestly Code and Holiness Code, but certain sections of the Bible, including the Book of Chronicles, Books of Samuel, and Book of Kings, also describe aspects of them. In the Holiness Code, the showbread is described as twelve cakes/loaves baked from fine flour, arranged in two rows/piles on a table standing before God; each loaf/cake was to contain two Omers of flour (Leviticus 24:5-6). The Biblical regulations specify that cups of frankincense were to be placed upon the rows of cakes, and the Septuagint, but not the masoretic text, states that salt was mixed with the frankincense; the frankincense, which the Septuagint refers to as an anamnesis, (a hapax legomenon), constituted a memorial (azkarah), having been offered upon the altar to God (Leviticus 24:7-9).
According to the Book of Chronicles, the Kohathite clan had charge of the baking and setting in order of the bread, suggesting that there were secret extra requirements in preparing the bread, known only to the Kohathites. Since leavened products were prohibited from the altar, and the cakes/loaves are not described as being offered upon it, it is possible that the showbread was leavened; however, as they were carried into the inner part of the sanctuary, it is highly probable that they were unleavened.
The cakes were to be left on the table for a week, and then be replaced with new ones on the Sabbath, so that there were always fresh loaves on the table, and those that had started going stale were removed; the Biblical text states that the Jewish priests were entitled to eat the cakes that had been removed, as long as they did so in a holy place, as it considered the bread to be holy. It appears that consumption of the bread wasn't the exclusive preserve of the priests, as the narrative of David's sojourn at Nob mentions that Ahimelek (the priest) gave David the holy bread, at his request.
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