Reference for Menachot 87:19

כל שאין לו מזוזה בפתחו עובר בשני עשה וכתבתם וכתבתם

and every priest who does not go up to the platform<span class="x" onmousemove="('comment',' To pronounce the priestly benediction.');">¹³</span> transgresses three precepts;<span class="x" onmousemove="('comment',' Cf. Num. VI, 23: On this wise ye shall bless the children of Israel; ye shall say to them, which contains two precepts, and the third in v. 27: So shall they put My name upon the children of Israel.');">¹⁴</span>

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