39 When Yosef and Miryam had finished doing everything required by the Torah of the Lord, they returned to the Galil, to their town Natzeret.
40 The child grew and became strong and filled with wisdom — God’s favor was upon him.
41 Every year Yeshua’s parents went to Yerushalayim for the festival of Passover. 42 When he was twelve years old, they went up for the festival, as custom required. 43 But after the festival was over, when his parents returned, Yeshua remained in Yerushalayim. They didn’t realize this; 44 supposing that he was somewhere in the caravan, they spent a whole day on the road before they began searching for him among their relatives and friends. 45 Failing to find him, they returned to Yerushalayim to look for him. 46 On the third day they found him — he was sitting in the Temple court among the rabbis, not only listening to them but questioning what they said; 47 and everyone who heard him was astonished at his insight and his responses. 48 When his parents saw him, they were shocked; and his mother said to him, “Son! Why have you done this to us? Your father and I have been terribly worried looking for you!” 49 He said to them, “Why did you have to look for me? Didn’t you know that I had to be concerning myself with my Father’s affairs?” 50 But they didn’t understand what he meant.
51 So he went with them to Natzeret and was obedient to them. But his mother stored up all these things in her heart.
52 And Yeshua grew both in wisdom and in stature, gaining favor both with other people and with God. 
Complete Jewish Bible (CJB)
Copyright © 1998 by David H. Stern. All rights reserved.
Again we have to ask about Luke’s sources. Ultimately, only Jesus’ family could have given this information. I think it has the feel of a legend, which Luke has very carefully adapted to suit his purpose, which is to guide the reader’s understanding of Jesus as God’s child. After all, how does God’s human child show his relationship with God? Indeed how does he know about God and his relationship with God?
Luke’s answer: he is brought up by his parents in the faith tradition of his people, but like any true learning this is not a passive process; he also contributes his own understanding of the tradition.
At 12 Jesus may have been considered a man, ready to take upon himself “the yoke of the Torah”. A father was responsible for the faith of his son until some such age. The specific custom of Bar-Mitzvah had not developed at that period, but doubtless there was some kind of family ceremony. Perhaps Jesus’ behaviour can be partially explained as his exercise of new religious responsibility as a child of Abraham, who made a journey of faith away from his parental home, and of Moses who received the Torah from God.
The journey to Jerusalem has overtones of Jesus’ final journey to that city, whereas the journey of his parents back to Jerusalem when they have lost him, has overtones of the journey of the two disciples away from Jerusalem to Emmaus after the crucifixion. In this case Luke carefully notes that they find him “after three days.” Surely a pattern is being established of the one who becomes lost to his human family because he is attending to his father’s affairs; but returns after three days. There is a hint here of the sword which is to pierce Mary’s heart. Jesus’ response to her is a variant of that deafness to family needs shown later in his ministry. In ordinary terms it is inexcusable, but Luke wants the reader to understand that the “father’s affairs” may make inhuman demands. Jesus’ subsequent obedience to his parents in Nazareth distinguishes his disobedience from any kind of teenaged rebellion.
For Luke, who almost certainly wrote after the destruction of the Temple in 70CE, the association of Jesus Messiah with the temple and its holy tradition, is vital to his view of the new faith spreading into the Gentile world from Jerusalem, and of Jesus himself as God’s dwelling place, no longer fixed in one location.
As naturally as the boy Samuel, whose story we know, Jesus enters the holy place and is happy to listen and speak. God’s truth for Jesus is never a possession; always, rather, a shared treasure. The Jewish tradition that God’s word may be the subject of debate was later maintained by Jesus, even when he acted as Rabbi to his disciples.
At the end of this chapter, Luke has succeeded in portraying the origin of Jesus and the prophet John his cousin, among families of messianic Jews whose women are especially passionate in their expectation. He uses the story of his virginal conception to emphasise that although Jesus is fully human, he is also “fathered” by God and is God’s child in a way that other human beings can only share through him. Jesus is born in poverty and his birth is celebrated by the poorest of working men, to show that God entrusts his child into hands which have not been corrupted by wealth and power. Most of all Luke shows in his opening chapters that the story of Jesus is rooted in the story of Israel, but is not limited by it.
Luke has also taught his audience to listen very carefully to his words and phrases, which set up a system of echoes throughout the story, which is as a whole an echo of the story of Israel, God’s servant.
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