Nicodemus ‘came to Jesus by night’: the night and darkness bring fears: for nothing to do we pray the Evening Collect. Some have said that Nicodemus was hiding in the darkness.
By day Nicodemus knows who he is. He has an identity. He is a Pharisee. He has a role and a reputation as a leader of the Jews. He is ‘Israel’s teacher’. But by night Nicodemus is confused: and so comes to Jesus to be illuminated.