St. Joseph was called by God to serve the person and mission of Jesus directly through the exercise of his fatherhood. It is precisely in this way that, as the Church’s Liturgy teaches, he “cooperated in the fullness of time in the great mystery of salvation” and is truly a “minister of salvation.”(21) His fatherhood is expressed concretely “in his having made his life a service, a sacrifice to the mystery of the Incarnation and to the redemptive mission connected with it; in having used the legal authority which was his over the Holy Family in order to make a total gift of self, of his life and work; in having turned his human vocation to domestic love into a superhuman oblation of self, an oblation of his heart and all his abilities into love placed at the service of the Messiah growing up in his house.”(22)
In recalling that “the beginnings of our redemption” were entrusted “to the faithful care of Joseph,”(23) the Liturgy specifies that “God placed him at the head of his family, as a faithful and prudent servant, so that with fatherly care he might watch over his only begotten Son.”(24) Leo XIII emphasized the sublime nature of this mission: “He among all stands out in his august dignity, since by divine disposition he was guardian, and according to human opinion, father of God’s Son. Whence it followed that the Word of God was subjected to Joseph, he obeyed him and rendered to him that honor and reverence that children owe to their father.”(25)
Since it is inconceivable that such a sublime task would not be matched by the necessary qualities to adequately fulfill it, we must recognize that Joseph showed Jesus “by a special gift from heaven, all the natural love, all the affectionate solicitude that a father’s heart can know.”(26)
Besides fatherly authority over Jesus, God also gave Joseph a share in the corresponding love, the love that has its origin in the Father “from whom every family in heaven and on earth is named” (Eph 3:15).
The Gospels clearly describe the fatherly responsibility of Joseph toward Jesus. For salvation-which comes through the humanity of Jesus-is realized in actions which are an everyday part of family life, in keeping with that “condescension” which is inherent in the economy of the Incarnation. The gospel writers carefully show how in the life of Jesus nothing was left to chance, but how everything took place according to God’s predetermined plan. The oft-repeated formula, “This happened, so that there might be fulfilled…,” in reference to a particular event in the Old Testament serves to emphasize the unity and continuity of the plan which is fulfilled in Christ. — from Redemptoris Custos (1989)