Parashas Bo · Shemos 12:4 · TT note 12
Torah Temimah on Shemos 12:4, note 12 (on אִישׁ לְפִי אׇכְלוֹ תָּכֹסּוּ) points to Zevachim 22b.
Sefaria — Exodus 12:4
Sefaria — Torah Temimah on Exodus 12:4
Sefaria — Zevachim 22b
E-Daf — Zevachim 22b
English: One who is tamei from a corpse does not send his Pesach, as it is written, “each according to what he eats you shall make your count.”
Derash of לְפִי אׇכְלוֹ: only one who can eat may be enrolled; a tamei person cannot eat and therefore cannot send the offering.
A person tamei from a corpse does not appoint a Pesach, because enrollment requires capacity to eat of it.