Being born exactly half a year before Christ, John the Forerunner by the exact time of his birth depicted his mission of preparing the way for the Lord. He was born at the time of the year (June 24) when the day begins to grow shorter after the summer solstice, whereas the Nativity of Christ occurs (December 25) when the day begins to grow longer after the winter solstice. These facts are an embodiment of the words spoken later, by the Forerunner, after the beginning of Christ’s preaching: He must increase, but I must decrease (John 3:30).
“The herald of the Sun, the Forerunner” was John the Baptist, who was like the morning star that announces the rising of the Sun of Righteousness in the East. Just as the very event of the Nativity of John the Baptist was the antechamber of the Nativity of our Lord Jesus Christ, so also the feast of the Nativity of John the Forerunner is also the antechamber of the feast of the Nativity of Christ. “The star of stars, the Forerunner, is born on earth today, from a barren womb, John the beloved of God, and manifests the dawning of Christ, the Orient from on high” (Glory at Lauds, of the Feast, June 24). “The whole creation rejoiceth at thy divine nativity: for thou wast shown forth as an earthly angel, O Forerunner and a heavenly man, proclaiming to us, the God of heaven incarnate” (Cantile Five of the Canon). “O Prophet and Forerunner of the coming of Christ, we honour thee lovingly but cannot extol thee worthily; for by thy birth thy mother’s barrenness and thy father’s dumbness were unloosed; and the Incarnation of the Son of God is proclaimed to the world.” (Troparion, Tone 4)