Three little points about the Finding of the Child Jesus in the Temple.
The Law of Moses stipulated that the Jews of old were to go up to Jerusalem to worship in the Temple three times a year.
The trip on foot from Nazareth to Jerusalem was long. It took a few days. It was not a journey for anyone younger than twelve.
The pilgrimage of the twelve-year-old Christ to Jerusalem was the first time the Lord Jesus ascended to the Temple on His own two feet. It was His first religious pilgrimage.