Tertullian

“ Since the Lord Jesus Christ sent the apostles to preach, (our rule is) that no others ought to be received as preachers than those whom Christ appointed; for “no man knoweth the Father save the Son, and he to whomsoever the Son will reveal Him.” [1] Nor does the Son seem to have revealed Him to any other than the apostles, whom He sent forth to preach—that, of course, which He revealed to them. ”