The word that stands out in today’s readings is “defile.” Our Lord uses it when he teaches that the things that can come out of us are the things that truly defile us, things like “evil thoughts, unchastity, theft, murder, adultery, greed, malice, deceit, licentiousness, envy, blasphemy, arrogance, folly.” Jesus adds that these things come from the heart, and because they do, they defile.

But what does this mean? These days, this word is commonly associated with becoming dirty or spoiled. Yet that’s not exactly what Jesus means. The Greek word for “defile” (koinoó) means more than just dirtying or spoiling. It has to be seen in comparison with holiness.

The New Testament word for holy (hagios) means to set apart. It’s sort of like setting clean dishes apart from dirty ones, or clean clothes apart from dirty clothes, but this too means something more. Holiness (hagios) means to be set apart for God, or dedicated to God. The saints are the best examples. St. Teresa of Calcutta, for instance, nobody was like her; nobody was ministering to the “poorest of the poor” like her. She was truly set apart. She was truly dedicated to God. She truly shows us the heart of holiness.

This word “defile” (koinoó) is the opposite of being holy, the opposite of being set apart. This New Testament word means making common, as in taking something set apart for God and returning it to the ordinary things not dedicated to God. In other words, when we defile ourselves, when we have evil thoughts, when we are unchaste, when we steal or are greedy, when we are envious or blasphemous or arrogant, we are not simply defiling ourselves in the sense of becoming spiritually dirty. Sin makes us common. Sin makes us not dedicated to God. Sin stops us from being set apart.

Furthermore, this word for “defile” implies that we are already holy, that we are already set apart for the glory of God and dedicated to him alone. When we defile ourselves through sin, we are like misbehaving children, not simply taking back something set apart for God and dedicated to him only, but also devaluing our dignity as a holy people whom God has already set apart in his love, as it says in the Psalms: “know that the Lord has set apart the godly for himself” (Psalm 4:3).

So, today, do not sin. Do not be common. Be holy. Be set apart for God.