155 Here καί (kai) has been translated as “but” to indicate the contrast.
156 Grk “he said to them.”
157 Grk “Why is it that you were looking for me?”
158 Or “I must be about my Father’s business” (so , ); Grk “in the [things] of my Father,” with an ellipsis. This verse involves an idiom that probably refers to the necessity of Jesus being involved in the instruction about God, given what he is doing. The most widely held view today takes this as a reference to the temple as the Father’s house. Jesus is saying that his parents should have known where he was.

In other versions

And he said to them, “Why were you looking for me? Did you not know that I must be in my Father’s house?”

“Why were you searching for me?” he asked. “Didn’t you know I had to be in my Father’s house?”

“Why were you searching for me?” he asked them. “Didn’t you know that it was necessary for me to be in my Father’s house?”

“But why did you need to search?” he asked. “Didn’t you know that I must be in my Father’s house?”

And he said to them, “Why were you searching for me? Did you not know that it was necessary for me to be in the house of my Father?”

And he said unto them, How is it that ye sought me? wist ye not that I must be about my Father’s business?

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