Commenting on the verse in which Jesus asks, "Whom do you say that I am?  And Peter said, The Christ of God", (Luke 9, 20), St. Ambrose of Milan (d. 397) takes the opportunity to urge his readers to put true faith in The Lord's identity.  The following comes from his commentary on the Gospel of St. Luke:

"Believe as Peter believed, that you may be blessed and may merit to hear the words, 'Flesh and blood have not revealed this to you, but my Father who is in heaven' (Matthew 16, 17).  For flesh and blood are not able to reveal anything except that which is earthly, but he who speaks of the mysteries of faith by the spirit does not do so by the teaching office of flesh and blood, but is established in divine inspiration.  Do not depend on the flesh, lest you draw out commandments of flesh and blood, and you yourself become merely flesh and blood.  For, he who adheres to the flesh is flesh.  But, 'He who adheres to God is one spirit' (1 Corinthians 6, 17).  And The Lord said, 'My spirit shall not remain in these men forever, for they are flesh' (Genesis 6, 3)."



St. Ambrose also throws light on the matter of the opinions of the crowds as to the identity of The Lord Jesus, and the distinctions between him and the men they thought he was:

"It is fitting that he did not wish the crowds to consider him to be anyone except Elijah, Jeremiah, or John the Baptist.  Was he Elijah?  After all, Elijah was caught up to heaven.  But Christ was not Elijah, for Elijah was caught up, but Christ came down.  Elijah, I say, was snatched up, but Christ did not consider it robbery for him to be equal to God.  Elijah was avenged by the fires he called for, but Christ chose rather to heal his persecutors.  Why did they think he was Jeremiah?  Because Jeremiah was sanctified in the womb?  But he was not Jeremiah.  Jeremiah was sanctified, but Christ sanctifies.  The sanctification of Jeremiah began from within a human body, but Christ was holy from the Holy One.  Why did the people think that he was John the Baptist?  Because John felt the presence of The Lord while still in his mother's womb?  But Christ was not John.  John adored in the womb, but Christ was the One adored.  John baptized with water, but Christ baptized with the Holy Spirit.  John urged repentance, but Christ forgave sins."