The people answered Him, "We have heard from the law that the Christ remains forever; and how can You say, "The Son of Man must be lifted up'? Who is this Son of Man?"
John 12:34
Surrounding context
12:33 This He said, signifying by what death He would die.
12:34 The people answered Him, "We have heard from the law that the Christ remains forever; and how can You say, "The Son of Man must be lifted up'? Who is this Son of Man?"
12:35 Then Jesus said to them, "A little while longer the light is with you. Walk while you have the light, lest darkness overtake you; he who walks in darkness does not know where he is going.