New International Version
One of the teachers of the law came and heard them debating. Noticing that Jesus had given them a good answer, he asked him, "Of all the commandments, which is the most important?"

American Standard Version
And one of the scribes came, and heard them questioning together, and knowing that he had answered them well, asked him, What commandment is the first of all?

Berean Study Bible
Now one of the scribes had come up and heard their debate. Noticing how well Jesus had answered them, he asked Him, “Which commandment is the most important of all?”

Douay-Rheims Bible
And there came one of the scribes that had heard them reasoning together, and seeing that he had answered them well, asked him which was the first commandment of all.

English Revised Version
And one of the scribes came, and heard them questioning together, and knowing that he had answered them well, asked him, What commandment is the first of all?

King James Bible
And one of the scribes came, and having heard them reasoning together, and perceiving that he had answered them well, asked him, Which is the first commandment of all?

World English Bible
One of the scribes came, and heard them questioning together. Knowing that he had answered them well, asked him, "Which commandment is the greatest of all?"

Young's Literal Translation
And one of the scribes having come near, having heard them disputing, knowing that he answered them well, questioned him, 'Which is the first command of all?'

Mark 12:28 Additional Translations ...