Luke 2:45

42 and when he became twelve years old, they having gone up to Jerusalem, according to the custom of the feast,

43 and having finished the days, in their returning the child Jesus remained behind in Jerusalem, and Joseph and his mother did not know,

44 and, having supposed him to be in the company, they went a day`s journey, and were seeking him among the kindred and among the acquaintances,

45 and not having found him, they turned back to Jerusalem seeking him.

46 And it came to pass, after three days, they found him in the temple, sitting in the midst of the teachers, both hearing them and questioning them,

47 and all those hearing him were astonished at his understanding and answers.

48 And, having seen him, they were amazed, and his mother said unto him, `Child, why didst thou thus to us? lo, thy father and I, sorrowing, were seeking thee.`