John 5:12-15 NRSV
They asked him, “Who is the man who said to you, ‘Take it up and walk’?” Now the man who had been healed did not know who it was, for Jesus had disappeared in the crowd that was there. Later Jesus found him in the temple and said to him, “See, you have been made well! Do not sin any more, so that nothing worse happens to you.” The man went away and told the Jews that it was Jesus who had made him well.
NRSV: New Revised Standard Version