New Living Translation
The people were surprised when they heard him. “How does he know so much when he hasn’t been trained?” they asked.

American Standard Version
The Jews therefore marvelled, saying, How knoweth this man letters, having never learned?

Berean Study Bible
The Jews were amazed and asked, “How did this man attain such learning without having studied?”

Douay-Rheims Bible
And the Jews wondered, saying: How doth this man know letters, having never learned?

English Revised Version
The Jews therefore marveled, saying, How knoweth this man letters, having never learned?

King James Bible
And the Jews marvelled, saying, How knoweth this man letters, having never learned?

World English Bible
The Jews therefore marveled, saying, "How does this man know letters, having never been educated?"

Young's Literal Translation
and the Jews were wondering, saying, 'How hath this one known letters -- not having learned?'

John 7:15 Additional Translations ...