Augustine does not hesitate to say (Retract., I, xiii, 3): "What we now call the Christian religion existed amongst the ancients, and was from the beginning of the human race, until Christ Himself came in the flesh; from which time the already existing true religion began to be styled Christian".
Whether due ultimately to the Old Testament predictions or to the fragments of the original revelation handed down amongst the Gentile, a certain vague expectation of the coming of a great conqueror seems to have existed in the East and to a certain extent in the Roman worlds, in the midst of which the new religion had its birth.
But a much more marked predisposition to Christianity may be noticed in certain prominent features of the Roman religion after the downfall of the republic. In their stead Greek philosophy occupied the minds of the cultured, whilst the populace were attracted by a variety of strange cults imported from Egypt and the East.
During his whole mortal life on earth, including the two or three years of His active ministry, Christ lived as a devout Jew, Himself observing, and insisting on His followers observing, the injunctions of the Law ( Matthew 23:3 ).
The sum of His teaching, as of that of His precursor, was the approach of the "Kingdom of God", meaning not only the rule of righteousness in the individual heart ("the kingdom of God is within you" — Luke ), but also the Church (as is plain from many of the parables ) which He was about to institute.
"I send the Promised of my Father upon you, but remain ye in the city till ye shall be clothed with power from on high" ( Luke ).
"John indeed baptized with water, but you shall be baptized with the Holy Ghost, not many days hence" ( Acts 1:5 ).
Yet, though He often foreshadowed a time when the Law as such would cease to bind, and though He Himself in proof of His Messiahship occasionally set aside its provisions ("For the Son of man is Lord even of the sabbath ", Matthew 12:8 ), yet, as, in spite of His miracles, He did not win recognition of that Messiahship, still less of His Divinity, from the Jews at large.
He confined His explicit teaching about the Church to His immediate followers, and left it to them, when the time came, openly to pronounce the abrogation of the Law.
Thus much may be said with regard to the remote preparation of the world for the reception of Christianity.