Charles Spurgeon Commentary John 1:38

"And Jesus turned, and beheld them following, and saith unto them, What seek ye? And they said unto him, Rabbi (which is to say, being interpreted, Teacher), where abideth thou?" — John 1:38 (ASV)

Then Jesus turned, and saw them following, and said to them, What do you seek?

Christ wants intelligent followers: so he asks the question, "What do you seek?"