Hath set to his seal, &c.— Hath made a most becoming and substantial acknowledgment of the veracity of God, who by his prophets in antient times foretold what the nature of the Messiah's kingdom would be; and who speaketh now to men by his only-begotten Son, in such a manner as he never did by any mere prophet. For he whom God hath sent,—that is, his only-begotten Son, speaketh the words of God; doctrines, which by their own native truth and light shew themselves to be the oracles of God: and which besides have the confirmation of the most extraordinary miracles; for God giveth not the Spirit by measure unto him. God has given him, as man, the inspiration of the Spirit, without those limitations and interruptions wherewith they were given to all other prophets whatsoever; for in sacred scripture, as well as in profane writers, to do, or give a thing by measure, is to do, or give it sparingly. See Ezekiel 4:16. Jeremiah 46:28. We may just observe, that it was customary among the Jews, for the witness to set his seal to the testimony which he had given.
Related Commentaries of John 3:33
John 3:33-34
33 He that hath received his testimony hath set to his seal that God is true.
34 For he whom God hath sent speaketh the words of God: for God giveth not the Spirit by measure unto him.