"And it killed a man or a woman": This is "extra," towards comparison and the formulation of a gezeirah shavah (identity) (as above). "the ox shall be stoned": Why is this stated? It follows a fortiori, viz.:If a tam is to be stoned, how much more so a mued! — No, this may be so with a tam, for which he does not pay kofer, but not with a mued, for which he does pay kofer. It must, therefore, be written "the ox shall be stoned."