The Lord had previously taught the people, both personally and by his prophets, that they should do all things in his name (see Moses 1:17; Moses 5:8; 2 Nephi 25:19; see also Robert L. Millet and Joseph Fielding McConkie, In His Holy Name, pp. 36-47).
With that as the foundation, Jesus now taught that it is not only reasonable but imperative that the Church be called after him. If it be called after a man, then it is a man’s church, but there is no salvation in a man’s church or in mortal works (see Russell M. Nelson, “’Thus Shall My Church Be Called,”’ Ensign, May 1990, pp. 16-18).