Another commandment: You shall not commit adultery. It seems pretty straightforward. But as with murder, Jesus teaches us that the sin of adultery begins in the heart, where all sin begins. No one wakes up in the middle of the night, trips, and falls into an adulterous relationship. Rather adultery tends to be cultivated, beginning with a lust for another person, the entertainment of fantasies regarding them, and then it is only a matter of time before those desires and intentions are acted upon. If we allow our hearts and minds to take on the character of a brothel, how much longer will it be until we begin living as though we are in one?
And so Jesus gives us some extreme advice: pluck out your eye, cut off your hand. Clearly He is not being literal, or the world would know that we were Christians by our disfigurements; I imagine converts to the faith would be few and far between. Rather Jesus is telling us not to negotiate with sin, that it isn’t worth distancing yourself from God because you think you have the strength to resist temptation to sin. This is precisely how temptation works; rarely does the Enemy try and convince us that running off with the neighbor’s spouse is a good idea. But what’s the harm in imagining them in certain ways? I’m not hurting anyone…
The Enemy, St. Ignatius tells us, is like a military commander, targeting our weaknesses. Frequent confession and the Daily Examen help us to familiarize ourselves with our weaknesses so that we can fortify against temptation. Sin—turning away from God—is nothing to be trifled with. It is absolutely poison; no one looks at cyanide and wonders “How much could I ingest before it is deadly?” Rather, they avoid it altogether. Think of the eye/hand example in this way: sin is a trap and snares us in our journey to heaven (2 Tim. 2:25-26), which is ultimately where we most long to be. Growing up in rural Iowa, there were people I knew who trapped game and sold the furs, and they would tell stories of checking their traps only to find a few toes, or the paw of a creature. This is not because the trap was too powerful and severed these appendages from the creature; rather the animal, in its powerful desire for freedom, literally gnawed off its own foot in order to escape. A gruesome example, true, but it illustrates the point well: it is better to take drastic measures to avoid sin than it is to sin. The love of God, and remaining in His love, is a greater good and pleasure than anything this universe has to offer us!