TT #24 · Parshas Shemini · Aliyah 2 · Passuk 20
Chabad.org — Vayikra Chapter 9 with Rashi
English: “They placed” and “they burned”: one priest may give the portions to another priest to burn them; the plural wording teaches that three priests are required, in keeping with “In a multitude of people is the king’s glory.”
Menachos 62a.
E-Daf.com — Menachos 62a (Tsurras Hadaf)
Textual inference — the wording “they placed” is understood in light of the plural participants and the principle of involving multiple priests in the service.
The differing verbs imply that one priest placed the portions while another burned them; the tradition derives a three-priest arrangement from “in the multitude of the people is the king's glory.”