“…the substance now rendered as “that which is leavened” (Exodus xii. 19) was, in reality, the Hebrew beer…”

…the substance now rendered as “that which is leavened” (Exodus xii. 19) was, in reality, the Hebrew beer, a substance resembling the present Arab bread-beer Boosa, a fermented and eatable paste of the consistency of mustard, and that the corresponding word, “nothing leavened,” in verse 20, was an eatable malt product, probably cakes sweetened by malt. The interpretation of the three words representing leaven and leavened products met with in the Hebrew Scriptures is admittedly unknown; in the English translation apparently needless repetitions occur. The division of leaven into distinct articles explains the raison d’étre of the so-called repetitions, and gives to the command a technical comprehensiveness hitherto unsuspected.

From this point, I proceed to argue that the identification in the account of the Exodus of a substance so purely Egyptian, as is Boosa, and which appears to be made in no other part of the world than the valley of the Nile, fully establishes the great antiquity of the ordination, and forms the strongest known argument in regarding such portion of the Scriptural account as relates to the command to abstain from leaven, as having been written from memoirs about that period, instead of having been handed down orally to the compiler in the time of Ezra.

The reader must dissociate from his mind all modern ideas of beer and brewing. I adduce reasons to show that the manufacture of beer was the earliest art of primitive man, an art exceeding in antiquity that of the potter or of the wine maker, and certainly that of the baker.

James Death, The Beer of the Bible: One of the Hitherto Unknown Leavens of Exodus (London: Trübner & Co., 1887), iii-iv.