Seal of God
The Jews speak much of the seal of God; which may not be impertinently remembered at this time. "What is the seal of the holy blessed God? R. Bibai, in the name of R. Reuben, saith, Truth. But what is truth? R. Bon saith, The living God and King eternal. Resh Lachish saith, Aleph is the first letter of the alphabet, Mem the middle, and Tav the last: q.d. I the Lord am the first; I received nothing of any one; and beside me there is no God: for there is not any that intermingles with me; and I am with the last."
There is a story of the great synagogue weeping, praying, and fasting; "At length there was a little scroll fell from the firmament to them, in which was written, Truth. R. Chaninah saith, Hence learn that truth is the seal of God."
We may easily apply all this to Christ, who is "the way, the truth, and the life," John 14:6: he is the express image of his Father, the truth of the Father; whom the Father, by his seal and diploma, hath confirmed and ratified; as the great ruler both of his kingdom and family.
(A Commentary on the New Testament from the Talmud and Hebraica, John Lightfoot)