The pesach-offering was slaughtered in three groups — for it is written: And the whole assembly of the congregation of Israel shall slaughter it (Exodus 12:6). [The verse mentions] “assembly,” “congregation,” and “Israel.”  The first group entered, [and when] the Temple Courtyard was filled, they closed the gates of the Temple Courtyard, and sounded a tekiah, a teruah, and again a tekiah. The Kohanim stood rows upon rows, and in their hands were silver bowls and golden bowls; one row was altogether of silver, the other row was altogether of gold; they were not mixed up together. Nor did the bowls have bases, lest they set them down and the blood congeal.