He that has received his testimony has set his seal to this that God is true.
All Commentaries on John 3:33 Go To John 3
Clement Of Rome
AD 99
Wherefore the Father bestows on him the glory and honour that was due and meet, putting on him the best robe, the robe of immortality; and a ring, a royal signet and divine seal,-impress of consecration, signature of glory, pledge of testimony (for it is said, "He hath set to his seal that God is true")