Following the previous Mishna (37a) that complimented the people whose contributions to the Temple enhanced its service, the Mishna on our daf lists individuals whose behavior was criticized by the Sages. Among them are two families of kohanim – Bet Garmu, who were responsible for baking the lehem ha-panim (shewbread) and Bet Avtinas, who were responsible for the ketoret (incense). The condemnation of both of these families focused on their refusal to share the knowledge of their craft with others.
The Gemara on our daf relates that in each case the Sages removed them from their positions and brought in experts from Alexandria in Egypt who were to teach how to do these things. In each case the experts could not create the same effect as the priestly families – they could not bake bread that would not become moldy, nor could they succeed in creating an incense whose smoke would rise in a straight line to the heavens – and the Sages eventually had to return them to their original positions – with a significant raise in their salaries.
In their defense, the baraita records their explanation for their behavior:
They said: The members of our father’s house knew that this house, the Temple, is destined to be destroyed, and they were concerned lest an unworthy man learn our skill of baking and go and engage in idol worship with that skill. Therefore, they attempted to prevent this skill from spreading beyond their family.
Rabbi Akiva records the story told to him by Rabbi Yishmael ben Loga, who once was picking herbs with the descendant of the Avtinas family, who began to cry and to laugh. He explained that he had seen the plant that was used to make the ketoret rise directly upwards, which reminded him of the loss of his family’s prestige, but encouraged him to believe that it would be returned one day in the future. When asked to point it out, he refused saying that the family had sworn never to reveal the secret to others.
The plant seen by the descendant of Bet Avtinas is referred to as ma’aleh ashan. Although the tradition identifying this plant has apparently been lost over the centuries, the generally accepted identification is with a weed called leptadenia pyrotechnica, a plant that grows in the southern part of the Jordan Valley and in the northern Sinai. This plant ignites very easily, and local Arabs have used it to make gunpowder and explosives. Lighting even one branch of the bush will cause it to burn up entirely in a very short amount of time, with flames reaching as high as ten meters.