Midrasz do Liczb 33:22

Our Rabbis have been taught: The house of Abtinas were skilled in preparing incense, but were unwilling to teach it. The sages sent for professional men from Alexandria of Egypt. These could mix the incense, but could not make it so that the smoke should not bend, while the smoke of the incense prepared by the former rose straight, like a rod; the smoke of the incense prepared by the latter was divided and bent hither and thither. When the sages heard of this, they said: 'All that the Holy One, praised be He! hath created, He hath created only for his glory, as it is said (Pr. 16, 4) Everything hath the Lord wrought for its destined end.' Hence the house of Abtinas had to be invited to resume their post. The sages sent for them, but they did not come; so the sages doubled their salary whereupon they came. Prior to their return, their wages amounted to twelve hundred dinarim a day, thenceforth they received twenty-four imndred dinarim; this is according to R. Meir. R. Juda, however, says that their previous salary was twenty-four hundred dinarim and thenceforth, forty-eight hundred dinarim.' The sages then inquired of them: 'Why are you unwilling to instruct others?' Whereupon they replied: 'Our family knows by tradition that this Temple is destined to be destroyed, and perhaps an unworthy person will learn it and go and serve idols thereby.' For the following they received praiseworthy mention: Never did a bride walk out of their house perfumed, and even when one of their house married a woman of another family, it was on the condition that she would not be perfumed, lest people say that they used the incense wherewith to perfume themselves. [This stand they took] to fulfil the passage (Num. 33, 22) And ye be thus guiltless before the Lord, and before Israel."