The best interpretation of "...lust after her hath committed adultery with her already in his heart," is that "in his heart" means PASSIONATELY, whole-heartedly. That there has already been adultery (like Jesus says), and that done in a very passionate, heart-full manner.
What is being pointed to is not just some passing fancy, and certainly NOT THE MERE THOUGHT that some woman looks "interesting."
Mt. 5:28 "But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart."
In contrast to "Thou shalt not commit adultery" Jesus the Christ is saying, if you look upon a woman to lust after her, that is indication you have already sinned.
The "lust" here is the same word that is used for "covet," the possessing of the object desired. ACTUAL ADULTERY. Not merely finding someone looks desirable.
The attraction of a man for a woman (and vice versa) is God-ordained and God created.
Find the other sex pleasing to the eyes and all that, yet NEVER HAVE THE LUST OF ACTUAL ADULTEROUS SEXUAL INTERCOURSE.
The lust that means one has already committed adultery, that is what is to be avoided, the "lust" that is part and parcel of actual adultery, its heart part.
DO NOT ever want to possess someone whom one is not married to with so much "heart" that the lust is indistinguishable from sexual intercourse. Don't let it happen, or the "lust" is adultery (or fornication).
A segment from my book concerning this point:
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The Salvation Enigma, pp. 92-95.
Concerning the adultery and lust issue, the confusion is even more severe. The common understanding of this passage leans towards sexual immorality of the mind, and has become an enormous stumbling block, especially for young men. Going back to my earliest days as a Christian, I remember being sixteen or seventeen years old. And for me and my friend, our understanding, as it was taught to us, was that we were committing adultery if the right girl in the right clothes made us think about sex for even the most fleeting of moments. I remember sharing the gospel at the Ft. Lauderdale beach with the youth group, and my friend and I spent the better part of the day making the joke, “I don’t see her. Or her. Or her,” as we’d hold our hands up to our eyes to block the view of young women in scant bikinis.
Although we should not seek to deliberately indulge such appetites, and should certainly strive to dwell on more appropriate thoughts, this common interpretation is about as far from what Christ meant as a thing could be.
[1]
To understand what he’s saying here, there are a few things that need to be understood. Jesus’ statement is loaded with implicit colloquialisms, masked by language barriers and two thousand years of cultural evolution. I may have to explain it to you, but he didn’t need to explain it to them. They understood exactly what he meant.
First and foremost, the context is adultery, not random sexual desire. This context doesn’t change after the initial statement, but is defined by it. While Christ may be elaborating on what constitutes culpability, he is still nevertheless talking about
adultery. And adultery, to those listening to him speak, was the crime of a man taking another man’s wife. Due to the polygamist culture of first century Judaism, the man’s marital status was immaterial to the scenario.[2] A married man who took another woman simply had an extra wife. But if the man took a woman who was already married, then it was the crime of adultery, whether due to the woman’s lack of fidelity, or the man’s presumptuousness in taking what belonged to his neighbor. Either way, the woman in the scenario had to be married for adultery to occur, while for the man it didn’t matter. It is only in our Romanized perspective of monogamy that a cheating husband is considered an adulterer.
The second point is the use and interpretation of the word “lust.” By definition, this English word merely refers to desire, and if the passage is interpreted according to that definition, the translation is accurate, if weak. The problem is that “lust” carries with it the connotation of
sexual desire in our own usage, causing most to mistakenly interpret this as a crime of mental fornication, which is unilaterally applied to any and all women, regardless of whether they are married or not. You see her, like her, are sexually attracted to her … you’ve had sex with her in your heart, which constitutes adultery by the strict interpretive understanding of the passage. However, the Greek word ἐπιθυμέω, from which “lust” has been translated, is also used by Paul in Romans 13:9 when listing the Ten Commandments, saying, “Thou shalt not covet (ἐπιθυμέω),” whereas his intent to portray sexual desire or passion employs the word πυρόω in 1 Corinthians 7:9. Better to marry than to burn (πυρόω).
What Jesus is associating with adultery here is the “coveting” of your neighbor’s wife. And covetousness is not necessarily sexual. Nor is it merely “to want” or “to desire” in the basest form. We all “want” things. That is the foundation of trade and commerce. Supply and demand. You “want,” and someone else “provides.” This is basic economics. I grow corn. You grow oranges. I “want” your oranges, and so we trade. I have not “coveted” my neighbor’s oranges.
For “you shall not covet” to be fulfilled by “love your neighbor as yourself,” as Paul says that it is, covetousness must, by necessity, affect your neighbor.
[3] And if it affects your neighbor, then it must have an outward manifestation that can be quantified. Love for your neighbor would have no bearing on the sin otherwise. The desires in our hearts and the thoughts in our heads do no ill until we choose to act upon them. So, to covet is not merely “to want,” which your neighbor will never know or suffer by, but to want something to such a degree that we attempt to obtain it, which
does harm them. Thus, to set your sights upon another man’s wife to “covet” her is to seek to obtain her.
Ergo, what Jesus is saying concerning adultery is that while the law says, “you shall not commit adultery,” if you
try to take her, the attempt makes you just as guilty. The effort is equal to the act, whether you succeed or not. Thus, it’s not the surreptitious look or the sexual thought that’s the problem, but the witty joke or inappropriate touch with the motive of eliciting a reciprocated attraction. In other words, it has nothing to do with them inadvertently attracting your attention, but about you deliberately attracting theirs to win their affection. That is what it is to covet your neighbor’s spouse, boyfriend, or girlfriend.
To reiterate, it is not my intent to suggest that it is okay for us to seek out or dwell on carnal things. All I’m saying is that that’s not what Christ is saying here. He’s telling us that to try to take someone’s wife — or husband, boyfriend, or girlfriend — is the same as actually doing so.
[1]. 2 Cor. 10:5; Phil. 4:8.
[2]. Matt. 5:27; Joseph.
AJ 17.14, 20.259-267; Justin
1 Apol. 134. Josephus, writing during the reign of Domitian, confirms the continued and accepted practice amongst the Jews to have multiple wives. Justin Martyr confirms that this continued to be the case.
[3]. Rom. 3:8-10.
