Matthew's genealogy makes evident the fact that Jesus was of the offspring of Abraham. It is as a son of Israel, God's Chosen People in the Old Covenant, to which he directly belongs.

Jesus is born among this people; he grows up in their religion and culture. He is a true Israelite who thinks and expresses himself in Aramaic according to the conceptual and linguistic categories of his contemporaries and he follows the customs and usages of his surroundings.

As an Israelite he is a faithful heir of the Old Covenant. "They are Israelites, and to them belong the sonship, the glory, the covenant, the giving of the law, the worship, and the promises; to them belong the patriarchs, and of their race, according to the flesh, is the Christ" (Rom 9,4-5).

Shortly after his birth, Jesus was circumcised according to the ritual prescriptions of the Mosaic Law, thus becoming officially a member of the people of the Covenant (Lk 2,21).

The mentions that "his parents went to Jerusalem every year at the feast of the Passover" (Lk 2,41), an indication of their fidelity to the Law and tradition of Israel.

Apart from this event, the whole period of the infancy and youth of Jesus is passed over in silence in the Gospel. It is the period of his "hidden life."

Jesus lived in his own family, in the house of Joseph, who took the place of a father in regard to Mary's son by assisting and protecting him and gradually training him in his own trade of carpenter.

The people of the town of Nazareth regarded him as "the carpenter's son" (cf. Mt 13,55). His fellow citizens asked with surprise, "Is not this the carpenter, the son of Mary? . . ." (Mk 6,3).

Besides his mother, they mentioned also his "brothers" and his "sisters", that is, those members of his kin ("cousins"), who lived at Nazareth. It was they who, as the Evangelist Mark mentions, sought to dissuade Jesus from his activity of teaching (cf. Mk 3,21).

Jesus' public ministry began at the age of thirty (Lk 4,16-17): "The Spirit of the Lord is upon me" (Lk 4,18). Jesus then announced, "Today this scripture has been fulfilled in your hearing" (Lk 4,21).

This way he brought about, in the scope of the one and the same divine Revelation, the transition from the "old" to the "new," not by abolishing the Law but by bringing it to fulfillment (cf. Mt 5,17).

It is with this thought that Hebrews opens, "In many and various ways God spoke of old to our fathers by the prophets; but in these last days he has spoken to us by a Son . . . (Heb 1,1).

This transition from the "old" to the "new" characterizes the whole teaching of the "Prophet" of Nazareth. A particularly clear example is the Sermon on the Mount. "Think not that I have come to abolish the law and the prophets; I have come not to abolish them but to fu/fill them" (Mt 5,17).

This "fulfillment" is a key word which refers not only to the teaching of the truth revealed by God, but also to the whole history of Israel, or of the people of which Jesus is a son. This extraordinary history, guided from the very beginning by the powerful hand of the God of the Covenant, finds its fulfillment in Jesus.