(Devarim 14:11) "Every clean bird you may eat": Because it is written (Vayikra 14:4) "And the Cohein shall command, and he shall take for the one to be cleansed (from leprosy) two birds," I might think that just as the slaughtered bird is forbidden (to be eaten), so, the sent-away bird; it is, therefore, written "Every clean bird you may eat (including the sent-away bird).