I am a fan of Agatha Christie books.
In one book, the detective Hercule Poirot says to his friend Hastings that it doesn’t matter whether the suspects tell him the truth; even when they are lying, he says, they are revealing themselves.
In today’s gospel Jesus tells us that it is what comes OUT of our mouths that makes us unclean, not what goes into it. This would have been a significant challenge to the Jews of the time, who had developed elaborate rituals around cleanliness. Here was Jesus saying that their rituals had very little to do with true goodness or holiness.
Have you ever found that something which slips out of your mouth reveals something unpleasant about you? Perhaps an insult that flies out before you can stop it, or a piece of gossip, or a criticism of another?
When this happens, we can use this experience to discover something about ourselves; that we are critical, or unkind, or pleased at the misfortunes of others. What comes out of our mouths has shown us where we are unclean. And that is a great gift, because we can ask God to clean us deep down in our hearts, the source of our speech. What has come out of our mouths shows us that we cannot make ourselves holy through elaborate rituals; we need God.