“And when they had fulfilled the days, as they returned, the child Jesus tarried behind in Jerusalem; and Joseph and his mother knew not of it.”
King James Version (KJV)
2:43 The child Jesus - St. Luke describes in order Jesus the fruit of the womb, #Lu 1:42|; an infant, #Lu 2:12|; a little child, #Lu 2:40|; a child here, and afterward a man. So our Lord passed through and sanctified every stage of human life. Old age only did not become him.
Lu 2:43 Fulfilled the days. The seven of the passover week. Jesus tarried behind. Luke neither tells us that Jesus remained behind at Jerusalem intentionally, nor that Joseph and Mary lost sight of him through want of necessary care. A circumstance must here have been omitted, and we may safely suppose that Joseph and Mary joined their fellow-travelers in the persuasion that Jesus, who knew of the time and place of departure, was among the younger ones.