I answer that, Among the Jews some were elders, and others of lesser degree. Now according to the author of De Qq. Nov. et Vet. Test., qu. lxvi, the elders, who were called "rulers, knew," as did also the devils, "that He was the Christ promised in the Law: for they saw all the signs in Him which the prophets said would come to pass: but they did not know the mystery of His Godhead." Consequently the Apostle says: "If they had known it, they would never have crucified the Lord of glory." It must, however, be understood that their ignorance did not excuse them from crime, because it was, as it were, affected ignorance. For they saw manifest signs of His Godhead; yet they perverted them out of hatred and envy of Christ; neither would they believe His words, whereby He avowed that He was the Son of God. Hence He Himself says of them (Jn. 15:22): "If I had not come, and spoken to them, they would not have sin; but now they have no excuse for their sin." And afterwards He adds (Jn. 15:24): "If I had not done among them the works that no other man hath done, they would not have sin." And so the expression employed by Job (21:14) can be accepted on their behalf: "(Who) said to God: depart from us, we desire not the knowledge of Thy ways."
But those of lesser degree---namely, the common folk---who had not grasped the mysteries of the Scriptures, did not fully comprehend that He was the Christ or the Son of God. For although some of them believed in Him, yet the multitude did not; and if they doubted sometimes whether He was the Christ, on account of the manifold signs and force of His teaching, as is stated Jn. 7:31,41, nevertheless they were deceived afterwards by their rulers, so that they did not believe Him to be the Son of God or the Christ. Hence Peter said to them: "I know that you did it through ignorance, as did also your rulers"---namely, because they were seduced by the rulers.