"Blessed be the Lord God of Israel, for he has visited and redeemed his people,
and has raised up a horn of salvation for us in the house of his servant David,
as he spoke by the mouth of his holy prophets from of old,
that we should be saved from our enemies, and from the hand of all who hate us;
to perform the mercy promised to our fathers, and to remember his holy covenant,
the oath which he swore to our father Abraham,
to grant us that we, being delivered from the hand of our enemies, might serve him without fear,
in holiness and righteousness before him all the days of our life.
And you, child, will be called the prophet of the Most High;
for you will go before the Lord to prepare his ways,
to give knowledge of salvation to his people in the forgiveness of their sins,
through the tender mercy of our God, when the day shall dawn upon us from on high
to give light to those who sit in darkness and in the shadow of death,
to guide our feet intothe way of peace."
The suggestion that John the Baptist was “set apart” and “marked out with a special favour” contains in itself the concept of an individual and specific mission that is entrusted to him. If that mission is in the first instant a mission directed towards the physical flesh of Jesus Christ, it also becomes in turn a mission in the mystical body of Jesus Christ that is the Church. The mission of John the Baptist is representative of a mission that continues in and is, in some measure, constitutive of the Church.
The words of the canticle of Zechariah, the “Benedictus”, used each morning in the Liturgy of the Hours, express this mission of John the Baptist in its ecclesial form.
The words of the first part of the canticle are focussed on God (the Father) and on the salvation that has come to us through his “visiting” of us in the person of the Son. The Baptist’s mission, like that of the Church, has its origin in the Father and the sending of the Son; and it has its purpose in pointing towards the Father through the Son. The mission of evangelisation in the Church, and indeed every aspect of the Church’s life and activity, needs to reflect the transparency towards the Lord that is part of John the Baptist’s charism:
There was a man sent from God, whose name was John. He came for testimony, toThe second part of the canticle directs us towards John the Baptist himself. In so far as it describes the office of the Baptist in announcing the presence of Jesus and his saving work, and in introducing Jesus to others, it describes a mission that in the Church now would be termed that of “evangelisation”. Indeed, it is possible to draw a close parallel between the verses of this second part of the canticle of Zechariah and the way in which the Church understands different stages in the work of evangelisation:
bear witness to the light, that all might believe through him. He was not the light, but came to bear witness to the light….
He must increase, but I must decrease.
you will go before the Lord to prepare his ways
Christian witness, dialogue and presence in charity
– is urged by charity, impregnating and transforming the whole temporal order, appropriating and renewing all cultures;
– bears witness amongst peoples of the new way of being and living which characterizes Christians;
(to give knowledge of salvation to his people) in the forgiveness of their sins, through the tender mercy of our God
Proclamation of the Gospel and the call to conversion
– proclaims explicitly the Gospel, through "first proclamation", calling to conversion
to give light to those who sit in darkness and in the shadow of death
Catechumenate and Christian Initiation
– initiates into the faith and the Christian life, by means of "catechesis" and the "sacraments of Christian initiation", those who convert to Jesus Christ or those who take up again the path of following him, incorporating both into the Christian community
to guide our feet into the way of peace
Formation of the Christian communities through and by means of the sacraments and their ministers
– constantly nourishes the gift of communion amongst the faithful by means of continuous education in the faith (homilies and other forms of catechesis), the sacraments and the practice of charity
you will go before the Lord to prepare his ways
– continuously arouses mission, sending all the disciples of Christ to proclaim the Gospel, by word and deed throughout the whole world.
This specific mission of John the Baptist therefore continues in the work of the Church for the evangelisation of the world.
The next day he saw Jesus coming toward him, and said, "Behold, the Lamb of God, who takes away the sin of the world! This is he of whom I said, `After me comes a man who ranks before me, for he was before me.' I myself did not know him; but for this I came baptizing with water, that he might be revealed to Israel." And John bore witness, "I saw the Spirit descend as a dove from heaven, and it remained on him. I myself did not know him; but he who sent me to baptize with water said to me, `He on whom you see the Spirit descend and remain, this is he who baptizes with the Holy Spirit.' And I have seen and have borne witness that this is the Son of God." 
 Lke 1:68-75
 Jn 1:6-8, 3:30
 Lke 1:76-79
 The table that follows compares the verses of the canticle to the presentation of the stages of evangelisation in the General Directory for Catechesis nn.47-48.
 Jn 1:29-34