And you shall give it to Elazar the Kohen, and he shall take it outside the camp and slaughter it before him.
Torah Temimah: Yoma 42b — Why does it say “osah”? “Osah” to Elazar, but for generations — [it may be done] by an ordinary Kohen.
English: Why does the verse say “osah”? “Osah” to Elazar, but for generations — by an ordinary Kohen.
Limitation of the specific address to Elazar versus the ongoing law.
Although the first para was given specifically to Elazar, for all subsequent generations any ordinary Kohen may perform the service.