"whether ox or sheep": to include (in the obligation of priestly gifts) kilayim (hybrids). "whether ox or sheep": (Priestly gifts obtain) both in Eretz Yisrael and outside of it. (Now why is a verse needed to tell us this?) Does it not follow a fortiori, viz.: There is liability here (for priestly gifts), and there is liability for the first of the shearing. Just as the first of the shearing obtains in Eretz Yisrael and outside of it, so, the priestly gifts! Or, go in this direction: There is liability here (for priestly gifts), and there is liability for terumath reishith (i.e., terumah gedolah, which goes to the Cohein). Just as terumath reishith obtains only in Eretz Yisrael, so, the priestly gifts!