Rabbi Yoshua ben Levi came upon Elijahthe prophet while he was standing at the entrance of Rabbi Simeron be Tohai’s cave.
He asked Elijah,’When will the Messiah come?’
Elijah replied, ‘Go and ask him yourself.’
‘Where is he?’
‘Sitting at the gates of the city.’
‘How shall I know him?’
‘He is sitting among the poor covered with wounds. The others unbind all their wounds at the same time and bind them up again. But he unbinds one at a time and binds it up again, saying to himself,
‘Perhaps I shall be needed: if so I must always be ready so as not to delay for a moment.’

(from Tracate Sanhedrin as quoted in Nouwen’s The Wounded Healer)