But let us consider the words which He addresses to His Father respecting us and in our behalf. “Thou hast hid, He says, all these things from the wise and prudent, and revealed them unto babes: Yea, O Father, that so it seemed good in thy sight.” For God the Father has revealed unto us the mystery, which before the foundations of the world was hidden and reserved in silence with Him: even the Incarnation of the Only-begotten, which was foreknown indeed before the foundations of the world, but revealed to its inhabitants in the last ages of the world.
For the blessed Paul writes, that “to me who am the least of all saints, has this grace been given, that I should preach among the Gentiles the unsearchable riches of Christ; and clearly teach them all, what is the dispensation of the mystery that for ages has been hid in God Who created all.” (Eph 3:8).
The great and adorable mystery of our Saviour was hidden therefore even before the foundations of the world, in the knowledge of the Father. And in like manner we also were foreknown and foreordained to the adoption of sons. And this again the blessed Paul teaches us, thus writing, “Blessed be the God and Father of our Lord Jesus Christ, Who has blessed us with every spiritual blessing in heaven in Christ, according as He has chosen us in Him before the foundations of the world, that we should be holy and without blame before Him, having foreordained us in love to the adoption of sons by Jesus Christ unto Himself.” To us therefore, as unto babes, the Father has revealed the mystery that for ages had been hidden and reserved in silence.
St. Cyril of Alexandria, Commentary on Luke, Homily 65, p. 277