Bishop Youssef “The God of the two Testaments is One, Who in the Old Testament

Old Testament foretold the Christ Who appeared in the New; Who by the Law and the Prophets led us to Christ’s school. ‘For before faith came, we were kept in ward under the Law,’ and, ‘the law has been our tutor to bring us to Christ’ (Gal. 3:24). And if you ever hear any of the heretics speaking evil of the Law or the Prophets, answer in the sound of the Savior’s voice, saying, Jesus ‘came not to destroy the Law, but to fulfill it’ (Mt. 5:17).”
St Cyril of Jerusalem (The Nicene and Post-Nicene Fathers: Second Series Vol. VII; Eerdmans pg. 26)