Reference for Menachot 196:17

אלא הכתיב יערוך אותו אהרן ובניו דמצדד להו אצדודי

- They were all made to face [the middle lamp].<span class="x" onmousemove="('comment',' Whilst the middle lamp alone faced the Holy of Holies.');">²¹</span> For it has been taught:<span class="x" onmousemove="('comment',' Meg. 21b.');">²²</span>

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