Luke 17:9

Doth he thank that servant..? — The words are spoken, of course, from the standpoint of the old relations between the master and the slave, not from that of those who recognise that master and slave are alike children of the same Father and servants of the same Master. In order to understand their bearing, we must remember how the subtle poison of self-righteousness was creeping in, even into the souls of the disciples, leading them to ask, “What shall we have therefore?” (Matthew 19:19), and to ask for high places in His kingdom (Matthew 20:21).