Reference for Menachot 123:6

והא קא משמע לן דבעינן שלשה כהנים משום דכתיב (משלי יד, כח) ברוב עם הדרת מלך:

THE TWO LOAVES AND THE TWO LAMBS OF PENTECOST. Our Rabbis taught: [It is written,] And the priest shall wave then, upon ['al] the bread of the firstfruits [for a wave-offering before the Lord upon ['al] the two lambs].<span class="x" onmousemove="('comment',' Lev. XXIII, 20. The Heb. usually connotes 'upon', but this term precedes 'the bread' and also 'the two lambs', hence the difficulty as to which was in fact 'upon' the other.');">¹¹</span>

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