This commandment is much questioned today. Our age tends to understands sex as a normal extension of dating and as an expression of intimacy which can be desacralized and severed from its traditional link to monogamous marriage. As our age sees it, sex can be used simply as an expression of sincere love, irrespective of any link to marriage and permanent commitment. 

This understanding, however, goes against the sixth commandment which, properly understood, undergirds some of the key foundational principles that can make us healthy. 

What is forbidden by this commandment? Just as with the other commandments, there is an obvious level: The sixth commandment forbids all sexual union except within a validly sanctioned, monogamous marriage. Hence it forbids fornication, adultery, prostitution, and rape. 

But its tentacles reach wider. It also forbids all deliberately induced sexual pleasure that is had outside of marriage, such as masturbation and pornography. 

Finally, the commandment forbids the trivialization of sexuality, that is, any attempt to desacralize sex so as to make it simply a source of pleasure and recreation, cut off from high symbols, a casual thing. Forbidden at this level, among other things, is lust, the attitude that sees another as a sex object, devoid of full personality and not to be accorded full respect. 

But the sixth commandment is more than series of “thou shalt nots”. Properly respected, this commandment helps nurture an understanding within which sexuality can be what the creator intended it to be, a powerful, life-giving, ecstasy producing, family building, soul stabilizing experience that gives us the delight for which we were made. But this needs explanation: 

What is sex? Etymology is not always important, but in this case it can be helpful. The word sex comes from the Latin secare, a verb that literally means “to cut off”. To be sexed is to be cut off. Thus, for example, if you were to take a chainsaw and saw a branch off a tree, you would, in a manner of speaking, have “sexed” that branch. It would now lie on the ground by itself, separate from the tree, cut off from the larger reality with which it once made a whole. Now, if that branch had self-awareness it would feel that separation. It would ache and long to be reconnected to the whole from which it has been cut off, sexed. Human sexuality is just that, an aching awareness of having been cut off, the burning sense of lying on the ground as one lonely little particle that needs to be in union with something larger than itself.

Thus, sexuality understood in this sense is more than just having sex. It is a dimension of our self-awareness, an all-embracing yearning inside of us within which we feel that we have been cut off and within which we hunger for union again with the whole. In sexuality we are haunted by the fact that we are one small fragment of something larger, that we are away from home, and that, above all else, we would like to go home. Hence, sexuality is a nostalgia, a drive, a fire, an erotic pressure for connection: connection in love to community, family, friendship, creativity, play, genital union with another person, and immortality. To have these in our lives is to sleep with someone; to not have them is to sleep alone, irrespective of how much or little sex we might be having. The sixth commandment tries to protect and nurture this understanding. 

Thou shalt not commit adultery! Patrick O’Connor captures some of the wisdom of the caveat when he writes: “Hormones, however, have social origins, intent and consequences. Private minutes of affection, celebrated in ecstatic interludes of spring freedoms, inevitably involve the families from which they come and the family toward which they are going.” Sex, at the end of the day, is more about families than about private honeymoons. 

Among all the things that the creator gave us, sex is perhaps the most powerful, beautiful, and life-giving. It is, however, when abused, also perhaps potentially the most destructive. Few things heal or hurt the soul as deeply as does sex. It is a sacrament when properly respected, a perversion when not. In either case, it is a powerful fire. The creator’s edict, to not commit adultery is, ultimately, a matter of respect. To keep the sixth commandment is to properly respect the sacredness, beauty, and the power of a great fire. To not commit adultery is to have our shoes off before the burning bush because we know that hormones have origins, both social and divine.