Now, that the very Lord Himself of all might, the Word and Spirit of the Father, was operating and preaching on earth, it was necessary that the portion of the Holy Spirit which, in the form of the prophetic gift, had been through John preparing the ways of the Lord, should now depart from John, and return back again of course to the Lord, as to its all-embracing original.
Tertullian
The Five Books Against Marcion, Book IV
Chapter XVIII