Midras Imamat 1:4: Sifra, Bamidbar Rabbah & Shir HaShirim Rabbah

1) "and he shall place his hand … and he shall slaughter": In the place (the azarah) where semichah is performed, shechitah is performed, and shechitah must follow immediately upon semichah. Just as semichah obtains only with those who are clean (from defilement), so, shechitah.

1) (Vayikra 1:2): "Speak to the children of Israel … (Vayikra 1:4) and he shall place his hand on the head of the burnt-offering" — The children of Israel perform semichah (the placing of the hands), and gentiles do not perform semichah. Now which measure is greater? That of tenufah (waving the devoted portions) or that of semichah? The measure of tenufah is greater. For tenufah obtains both with things that have a spirit of life (i.e., animals) and with things that do not have a spirit of life (e.g., first-fruits, the two breads, etc.), whereas semichah obtains only with things that have a spirit of life. If I exclude them (gentiles) from tenufah, the greater measure, (as the Torah does, indeed, exclude them), should I not exclude them from semichah, the lesser measure! (so that the exclusion verse for semichah would seem to be superfluous) Perceived thus, tenufah is (indeed) the greater measure, and semichah, the lesser. But perceived otherwise, semichah is the greater measure and tenufah, the lesser. For semichah obtains with all partners (to the offering), but not tenufah. If they (gentiles) are excluded from tenufah, the lesser measure, would I (without the verse) exclude them from semichah, the greater? So that because there obtains with tenufah what does not obtain with semichah, and with semichah, what does not obtain with tenufah, it must be written "Speak to the children of Israel, etc." — The children of Israel perform semichah, and not the gentiles.

“Each at his banner,” that is what is written: “You are beautiful, my love, like Tirtza” (Song of Songs 6:4); as I accede [mitratze] to you. Alternatively, “like Tirtza,” you accede to Me. Alternatively, “like Tirtza,” that you gain acceptance through offerings, as it is stated: “So that it will be accepted [venirtza] for him, to atone for him” (Leviticus 1:4).
“Lovely like Jerusalem” (Song of Songs 6:4), like those groups of ministering angels that fear Me and are wholly devoted to Me. “Formidable like banners” (Song of Songs 6:4); in what way are you like banners? With the banners that I gave you. David sees and says: “He did not do so to every nation” (Psalms 147:20), but rather to His people; that is what is written: “Each at his banner….”