They see some of his disciples eating without washing their hands. Mark then explains to his audience the Jewish custom of washing before dinner, indicating a non-Jewish audience. The Expositor's Greek Testament speaks of Mark writing "from the Gentile point of view"; the Cambridge Bible for Schools and Colleges suggests the explanation was "for Roman readers". The Pharisees and scribes ask Jesus why they are not obeying the custom and Jesus replies with a quote from Isaiah 29:13 and tells them "You have let go of the commands of God and are holding on to the traditions of men". He rebukes them for letting a man who makes an offering to God, i.e. money to the priests, no longer help his parents, in violation of the fifth commandment. That this was done is not found in other sources of the period, although "...rabbinic Jewish texts suggest that vows may be broken in such circumstances." (Miller 29)