Matthew 23:25

“Woe to you, scribes and Pharisees, hypocrites! for you cleanse the outside of the cup and of the bowl, but within they are full from extortion and excess.”

Note that this parallels those who lay great weight on their own gifts and offerings, which have a derived holiness, rather than on what is intrinsically holy (Matthew 23:16). That prevented them from genuinely approaching the living God. Here their fault lies in cleansing externals while not being concerned about what lies beneath, and thus failing to please God. In both cases it is to miss what is essential for the sake of the inessential. They laid great stress on the ritual cleansing of pottery, and of their own outer bodies, but they ignored what lay within themselves and were thus full of ‘extortion' (obtaining things by false means) and ‘excess' (lack of self-control, self indulgence). It is not, of course, that the Scribes and Pharisees were particularly evil men. They simply indulged in the same corrupt practises as many others. The difference lies in the fact that they set themselves up as the standard by which others should be judged, and as the custodians of the people's morals, and should thus have been a glowing example to others. But they were not. Their light should have been shining before men (Matthew 5:16), but instead it was dimmed and distorted. When we call ourselves Christians we too have to beware that our lives are consistent with what we believe, or we too will come under the same condemnation.

The picture of the Pharisee carefully cleaning the outside of a vessel while at the same time it was full of filthiness, without bothering about the inside, is probably intended to be amusing as well as telling. Jesus constantly uses caricature to get over His point. But in the application the vessel is themselves, keeping their outsides clean with constant washings, and yet not worrying about the inner heart. It was certainly typical of much of what they did, and much of what many of us do.