The Eucharistic liturgy, as described in the Didache or “Teaching of the Twelve Apostles” (ca. AD 50-70), contains prayers over the bread and the wine (mixed with water), which read as follows:
We thank you, our Father, for the holy vine of David your servant, which you have revealed to us through Jesus your Child. Glory be yours through all ages!
We thank you, our Father, for the life and knowledge which you have revealed to us through Jesus your Child. Glory be yours through all ages!
What is the purpose behind referring to Christ as a “child?” The Greek word being used is pais, which can mean both “servant” and “child” (son, if you will), depending upon the context. By calling Christ the pais of the Father, a double-meaning can be inferred.
First, that Christ is the suffering, anointed (Messianic), “Servant” in the prophecy of Isaiah, which, at this point in the history of the apostolic Church, was a primary “gospel” text. It even came to be known as “the fifth gospel.” Jesus is being identified as the “Servant of the Lord” (e.g. Isaiah 42:1-9; 49:1-6; 50:4-11; 52:13-53:12), in fulfillment of Isaiah’s prophecies.
Secondly, that Christ is the “child” or “son” of God the Father. As with the Greek, the Hebrew word for “servant” (ebed) can also mean “child” or “son.” Jesus is not only the suffering Christ and Servant of God, but is also his only-begotten Son, by virtue of his resurrection from the dead (Rom. 1:4). And if Christ is both servant and Son of God, so too is his Church:
The fact that the figure of the Servant of God in Israel was both individual and collective suggested the ecclesial dimension of the vocation of Jesus, who carries the entire community of the faithful with him in his passion and resurrection. The term “child” as applied to Jesus in the earliest Christian texts is associated with this entire range of history and theology.
Lucien Diess, Springtime of the Liturgy, p. 75