Hilary of Poitiers

Or; Seeing beforehand that there would be many who would only glory in the name of Apostleship, but in their whole life and walk would be unworthy of it, He does not therefore deprive of its reward that service which might be rendered to them in belief of their religious life. For though they were the very least, that is, the greatest of sinners, yet even small offices of mercy shewn them, such as are denoted by the cup of cold water, should not be shewn in vain. For the honour is not done to a man that is a sinner, but to his title of disciple.