What Catholics Believe - Chapter Thirty-Three

The Ninth Commandment:  Practice Purity of Heart

Of the Ten Commandments, the last two may be least well-known and perhaps even taken for granted. They deal with issues that are more subtle and that we most likely would not necessarily detect, even in people who don’t bother living up to the demands of these commandments.  If someone kills or lies or steals, it becomes a public offense, but if people are thinking and desiring evil but don’t tell anybody, the sinfulness is hardly ever evident unless it is revealed by the sinner.  Though we don’t reveal our own sinful desires, and will most likely never know the evil thoughts in the minds and hearts of others, it doesn’t mean that there is no sinfulness or that these feelings in the recesses of our hearts don’t seriously affect our spiritual lives.

The last two commandments call us to a high level of integrity, and without this integrity, we cannot be faithful followers of Jesus.

Focusing on the Ninth Commandment, “thou shalt not desire thy neighbor’s wife,” may I reflect  on the integrity I’m talking about?   

Is it because one is doing something that no one knows about and therefore doesn’t cause public scandal that a bad action isn’t seriously sinful?  If a man is cheating on his wife and convinces himself it’s o.k. because this affair is mutually acceptable and isn’t known by his wife or anybody else, is he less guilty?  This husband might seem to be a wonderful family man and provider, attending Mass every Sunday and passing for an ideal Christian; any of us finding out what is going on secretly would be even more scandalized and experience the hurt of deception.

I now invite you to see how purity of heart means not allowing even our most intimate thoughts and desires to go against the principles and values we try to live by in public. For the spouse who wants to be totally faithful, for anyone of us who wants to live up to the ninth commandment, along with its approval and refinement given to us in Jesus’ own words, the purity of the inner chambers of our hearts has to match the purity of our words and actions. Neglecting one or the other can have serious consequences. Integrity, growth in holiness, demands that purity be present in both our public words and actions, as well as in our most intimate thoughts and desires.

Some might convince themselves that as long as they only think and desire impurely, all is well. I seriously question how anybody could possibly be prayerful and truly loving when one’s mind is busy with thoughts and desires that are incompatible with God’s ways.

I realize that “purity of heart” isn’t limited to sexual matters. Any evil thought, including hatred, vengeance, greed, undue attachment, resentment, discrimination and so on, affects our purity of heart. However, it might be hard to imagine that, at some point or other in life, one has not been preoccupied with sexual thoughts or desires. We must, of course, make sure that the distinction is made between temptation and sin. Temptation is always the unwanted thought or desire that we refuse to dwell on. I’ve known people who have struggled with “bad thoughts” and are people with a high level of purity of heart because of their vigilance to ward off such thoughts. One’s virtuous life actually grows in the context of such struggles.

The ninth commandment in the Old Testament and Jesus’ teachings in the New Testament remind us that our Catholic tradition has much to tell us about our human nature. Unless we live a good and pure life in our minds, we will not be wholesome human beings.

If we believe that our hearts and minds are temples where God resides, we know full well that such a temple cannot welcome anything impure, anything incompatible with the holiness of God within us.