Why does the Church celebrate the Nativity of John the Baptist? Only three birthdays are celebrated on the Church’s liturgical calendar, the Nativity of Our Lord (December 25), the Nativity of His Mother (September 8), and the Nativity of His forerunner, John the Baptist, on June 24. Saint John the Baptist was set apart from the womb to prepare the way of the Lord and was a significant figure connected to the Incarnation and the Redemption. The Church honors him because of his role in preparing the way for Christ. https://www.ewtn.com/catholicism/seasons-and-feast-days/nativity-of-saint-john-the-baptist-23956