Reference for Yoma 38:6

א"ר זכריה בן קבוטל וכו' מתני ליה רב חנן בר רבא לחייא בר רב קמיה דרב א"ר זכריה בן קפוטל ומחוי ליה רב בידיה קבוטל ונימא ליה מימר ק"ש הוה קרי

Some say: He was smitten as he came out [of the Holy of Holies]. For R'Hiyya taught: Some sort of a noise was heard in the Temple Court, for an angel had come and struck him down on his face [to the ground] and his brethren the priests came in and they found the trace as of a calf's foot on his shoulder,<span class="x" onmousemove="('comment',' [The high priest, in coming out of the Holy of Holies, walked backward so as not to turn his back on the Holy of Holies (v. infra 52b) . When he reached the threshold and his back first emerged behind the curtain, the angel who was outside the curtain struck him on his back between the shoulders and threw him down, making him fall forward into the Holy of Holies with his face to the ground. There he lay till his brother priests came and threw him out. Cf. J. Yoma, I, 5. Lauterbach J.Z. HUCA IV, p. 193.]');">¹⁰</span> as it is written: And their feet were straight feet, and the sole of their fe was like the sole of a calf's foot.<span class="x" onmousemove="('comment',' Ezek. I, 7. That trace is the 'evidence' that an angel had struck him, kicked him with his foot. The 'four living creatures' are identified with angels.');">¹¹</span>

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