Normally, the Church only ever celebrates the anniversary of a saint's death, regardless of how significant he or she was - for example, the anniversary of Paul's and Peter's deaths next week. Why is it different now with St. John? Why do we also celebrate his birth and why does this feast even take a higher position than that of his martyrdom?
Incidentally, there is only one other saint for whom we celebrate not only the day of her death but also her birthday, and that is the Mother of God. In the case of the Mother of God, it is easy to understand: she was conceived without original sin and her birth represented the key to the salvation of all humanity, as she is the one through whom Christ came into this world. But why is such importance attached to the birth of Saint John? Scripture records that at the moment Mary and Elizabeth met, Elizabeth was filled with the Holy Spirit and the child did a leap of joy (cf. Lk 1,41). Tradition has interpreted this dancing movement of St. John to mean that he was already freed from original sin in his mother's womb. The first reading from the Book of Isaiah, therefore, speaks of this sanctification in the womb: "The LORD called me from birth, from my mother's womb he gave me my name. " (Jes 49,1). John is the only saint who was freed from original sin while still in his mother's womb, and so he came into the world perfectly sanctified, perfectly restored, with a perfect inner harmony of mind, will and emotions that allowed him to work entirely in harmony with God's grace. This extraordinary grace was given to him to enable him to prepare Israel to meet the Lord.
How did he do that? He preached repentance and conversion. St. John is, so to speak, the bridge figure between the Old and New Testaments. On one hand, he is the last of the great Old Testament prophets who call us to repentance with a powerful voice. At the same time, however, his unique role as the forerunner of the Messiah places him squarely in the New Covenant. Instinctively, we may be a little afraid of him because he can seem like a superhuman. Jesus said yes: "Amen, I say to you, among those born of women there has been none greater than John the Baptist; yet the least in the kingdom of heaven is greater than he." (Mt 11,11) He lived his whole life in the desert, drank no wine, ate only locusts, wore a penitential robe and was not afraid to testify to the truth of God's commandments, especially the indissolubility of marriage, with the surrender of his own life - a saint seemingly unattainable for us.
Nevertheless, we should not be afraid of him, because the real core of his message is not punishment but the mercy of God. In the Gospel, we hear how John got his name. Among the Jews, the newborn child always bore the name of the father or grandfather and thus received it in time. So after John's birth, Elizabeth tells the relatives what his name should be. They are astonished since no one in their family is called by that name. Then Zacharias is questioned and he confirms the name, for it was revealed to him by an angel. Why should Saint John have this name? In Hebrew, John is called "Jochanan" (יֹוחָנָן jôḥānān) and means "God is gracious". In the fact that John calls us to repentance lies the revelation of all God's mercy. After all, repentance would be of no use if God did not forgive our sins. Thus, St. John's primary task is to lead us to the experience of divine mercy.
A very important word in the Scriptures says: "All have sinned and are deprived of the glory of God." (Rom 3,23) Every human being has the same problem: we are captives of our passions. We come into the world with a fallen nature and need to realise that it is not God who suffers from our sin in the first place - which of course he does because he went to the cross for it - but us because it distances us from God. The whole Old Testament tells of how the people of Israel, because of their sin, repeatedly get into the most terrible situations from which God then saves them, when they are ready to repent, through the forgiveness of their sins.
The story of the people of Israel is a symbol for our own lives: We are slaves to sin and God wants to free us from it because he wants us to live in the freedom of God's children. He wants us to live in joy and not suffer the consequences of our bad deeds. That is why John the Baptist is a gift of God's mercy in our lives. He wants to lead us back to God so that we can be healed, to become fully free and alive human beings and to attain the greatness to which he has called us.
St. John is the Bride Guide, that is, he leads the People of God, the Bride of the Messiah, to which each one of us belongs by virtue of Baptism, to the Bridegroom. But the bride - as was the custom in ancient times and still is in other ways - must be washed and adorned before the wedding. And this is exactly what John does, calling us to repentance and leading us to the bath of rebirth by being wedded to the Lord (baptism). This purification is renewed in every confession. That is why on this day we celebrate his birth in a special way and already throughout the centuries so that his voice does not cease to sound, calling out: "Be reconciled to the Lord and receive the gift of his mercy!" ∎