I recently heard Joe Dallas speak at a seminar. He's a good speaker, though like so many evangelicals he seems to have reached his conclusions before even beginning to interact with the data.
He did use an analogy that I thought worked pretty well, when he compared sexual promiscuity to fast food. Fast food, though filling, lacks many of the nutrients that a body needs to function healthily; likewise, promiscuous behavior satiates the sex drive for a time but ultimately leaves unmet a person's need for genuine intimacy. Of course Joe would lump all gay relationships in with heterosexual promiscuity, which seems to have more to do with his pre-drawn conclusions than it does with any actual evidence, but in terms of promiscuity (on either side of the aisle) his analogy works well enough.
Of course, it also works pretty well as a case for categorizing the consumption of fast food as sin. After all, God designed our bodies to work a certain way, and that design extends well beyond the sexual aspects of our being. Sexual sin may get considerably more attention in the Bible, but then again how much attention can we expect people to pay to nutrition in an era when most people lived at (or just slightly above) subsistence level? When the New Testament authors declared that all food was 'clean,' they were commenting on the Old Testament's purity laws, not on whether all foods were equally beneficial to one's physical health.
Our bodies, after all, are temples of the Holy Spirit, and as such we have a moral duty to treat them properly and with respect; to do otherwise can only be sin. And what are some of the ways in which we sin on a habitual basis?
-We routinely consume 'junk' foods (chips, burgers & fries, soda pop, candy bars, etc.) in large quantities, even though these substances are largely or entirely devoid of nutritional value and are a major source of many of the health problems our society faces today (heart disease, obesity, diabetes and a host of other illnesses).
-We spend our days sitting at desks, driving cars, watching TV and otherwise being largely inactive for hours or days at a time. Our bodies need the daily workout that comes from frequent walking and physical labor, and few of us adequately make up for it through our leisure activities.
-We fly around the globe on a regular basis, traveling distances in hours that used to take weeks or months to cover. As miraculous as this ability is, the sudden change in time zones is disruptive to our bodies’ internal clocks and deleterious to our health. We can bounce back quickly enough from the occasional long-distance flight, but those who travel those distances on a routine basis risk damaging their health in a very real way.
-We deprive our bodies of sleep, getting to bed late and then forcing ourselves to get up before we’re fully rested, and then we make up for that deficit by jolting our bodies awake with caffeine. Even if we sleep in on the weekend we never fully make up for that lost time.
-We fill our minds with an overload of information on a daily basis through television, radio, newspapers and magazines, and now the internet. As a result we seldom take the time we really need to pause and reflect on all of this new data.
-We treat every ailment by reaching for the latest pharmaceutical drug, going for the 'quick fix' instead of giving our bodies what they need to heal themselves. What we gain in short-term relief we more than pay for in long-term side effects.
-Our environment is filled with toxins: air pollution, pesticides, heavy metals, preservatives, artificial sweeteners, synthetic hormones and many other unnatural substances. Over time these things build up in our bodies and cause (or compound) a host of health problems.
Our bodies are wondrously designed to tolerate and compensate for such things, within limits, but when they become part of our regular lifestyle, we eventually overwhelm the body's ability to protect itself.
One can argue that the above activities are not specifically prohibited by the Bible while same-sex relationships (allegedly) are, but all the same we are polluting God’s temples with each one of them. The damage we do to our physical bodies spills over into our mental and emotional states and ultimately limits our effectiveness for God’s work. How can we not categorize such neglect as sin?
The design argument cuts both ways. If God's standards hold us to acting only within the strict parameters of His original, ideal design for our bodies, how can we say that this standard doesn't apply across the board? What makes us think we can compartmentalize activities whose effects spill out into every aspect of our lives? What makes us think that a God of absolute purity wouldn't care about all the ways we pollute our physical bodies?
Of course, such a call for holiness wouldn't go over very well in most churches...