Rashi on Leviticus 16:10/רש"י על ויקרא ט״ז:י׳

1חי ‎יעמד SHALL BE PRESENTED ALIVE — חי‎ יָעֳמַד is the same as חי ‏‎ ‏ יוּעֲמַד (i. e. יָעֳמַד is a regular Hophal-form) — it shall be made to stand by others (i. e. it shall be placed). The Targum also renders it by: יתקם כד חי, “it shall be made to stand in a live state". — Why is it stated that it shall be presented alive; this is already implied in the word יעמד. it shall be made to stand!? But because it continues “to send it forth unto Azazel" and I would not know whether this “sending forth” means to death or to life (in the latter case it would mean “to let it go”; cf. Leviticus 14:7 where ושלח has this meaning), therefore Scripture states “it shall be presented alive” — its presentation must be made whilst it is alive and the animal remains so up to the time when it is being sent forth; it follows therefore that it shall be sent forth to death (Sifra, Acharei Mot, Chapter 2 6).

2לכפר עליו THAT HE MAY MAKE AN EXPIATION WITH IT — i. e. that he (the High-Priest) shall confess upon it (upon its head) Israel’s sins, as it is said (v. 21) “And Aaron shall confess upon it [the iniquities of the children of Israel]” (cf. Yoma 40b).