By Anthony Esolen

"Let your yes be yes and your no be no," says Jesus, commanding his disciples never to swear. "Everything else comes from the evil one."

Jesus is no casuist. We do not catch him saying it is all right to walk past a man suffering in the ditch, so long as you have something important to attend to. He does not say you may hate your enemies if you have cause. He does not say you may let your eyes go wild with lust, if only you restrain your hands.

We do not even catch him laying conditions on whether or when it is permissible to put away your woman. I phrase it that way, rather than "to divorce your wife," because in both Hebrew and Greek - as in German, and many other languages - the words for "man" and "woman" do further duty as "husband" and "wife," binding together biological and social realities.

A man can no more be a wife than he can be a woman. A man can no more be a woman than a human being can be a beast; though he can mimic their behavior, badly.

So when Jesus forbids putting away your woman, in one of the accounts he appends a parenthetical phrase, "except on account of porneia." I take that to mean, "I am not speaking about fornication," in which case putting away your woman as a woman is not the same as putting away your woman as a wife. That is not a condition but a clarification.

In any case, the words of Jesus are truly a two-edged sword, cleaving between the marrow and the bones. He makes sharp distinctions, not to split hairs but to set apart what human beings want to confuse. He is the Creator, who in the beginning created by distinguishing, dividing light from darkness, day from night, earth from sea, the birds from the creatures of the sea, the beasts of the field from one another in their distinct kinds, and man from the beasts; and when he created man, we get the first mention of male and female, distinct, meant for one another in sexual union.

The creation of Adam and Eve is a most powerful instance of both distinguishing and joining, and Jesus cites it in his sharp and clear dismissal of divorce: "For this reason a man shall leave his father and mother and cleave unto his woman, and they two shall be one flesh."

The stress is upon the adjective one, occupying the final and climactic position in the Hebrew sentence: to violate the union of man and woman in marriage is like violating the prime command: "Hear, O Israel, the Lord, the Lord your God, is One."

What do people most often lie about? I am not speaking of prevarications or false witness. I mean the lies we tell ourselves, to blunt the truth, to fog up our vision, to muddle the reason, to lull the conscience into a doze.

We lie about things that whet our appetites: power, money, vengeance, prestige, sex. A power-hungry man is the last person we should trust to give a fair account of his political maneuvers. We would not find it pleasant to go over the books of a covetous man, even if he managed to remain always within the law. And someone who has made a habit of sexual sin - who has cast it in bronze and raised it up as an image of his most precious self? Why should we trust him?

"God is not the author of confusion," says Paul. The word for "confusion," akatastasia, suggests an inability to sit still: uprising, tumult, disorder, breaches of inward and outward peace.

All sin is an uprising against order. All sin a lie. God is truth - solid as rock, dependable, immovable. But the lie is vague, indirect, cunning, shifty, like the sands beneath the houses we build when we do not build them on the words of Jesus.

Satan, says Jesus, was "a murderer from the beginning," and "a liar, and the father of lies." How can you be a "father of lies"?

I take the phrase at its face value. God commanded the creatures of the earth, and then Adam and Eve, to "be fruitful and multiply," Adam to be the father, Eve "the mother of all the living." They are ready. They are naked, and not ashamed.

Then comes the serpent with his manifold lie, his insinuat...