מילון על זכריה 13:12

Once Rabbi Jehudah was asked concerning the Trinity and the verse of Zechariah (13:8) was quoted that “it shall come to pass that in all the land two parts therein shall be cut off and die but the third shall be left therein.” Some Christians explained this verse to indicate that those people who believed in two kinds of gods, such as the Persians who believed in a god of light and a god of darkness, shall perish and only those who believed in the Trinity would be saved. Rabbi Jehudah agreed with them concerning the Persians but the “third” he explained to refer to the Jews who are made up of three groups (Priests, Levites and Israelites) and who praise God by thrice saying Kadosh.²¹⁾דברים רבה פּרשה ב׳ פּיסקא כ״ד.