It's been...what...over 15 years since I ate meat. Initially, it was more a question of convenience than anything else. When you marry a vegetarian, you've got to be motivated to prepare your own meat for meals. And I wasn't. Just too lazy. I'd eat meat when we went out, though. Like this insanely delicious steak salad at the Little Viet Garden in Arlington. Cubes of steak marinated in red wine, salt, and garlic, placed hot atop a bed of cool crisp greens. It's been ten years, and I still have Pavlovian slobber in my mouth at the thought of it.
But the more I thought about it, the more I thought theologically about it, the less I was able to sustain it.
From the standpoint of our God-given stewardship over creation, I couldn't justify it. We are given dominion, sure. But the purpose of that dominion was to exercise care over the Eden into which God placed us. Eating the flesh of other creatures was not a part of that plan, or part of what God called good (Gen. 1:29). If in Christ I am a new creation, and if Christ's work in me is to restore the breach established by our fall from Eden's grace, then not eating meat can be one way of personally affirming the healing of that rift.
Further, I feel that it is my responsibility as a Christian to minimize the amount of hurt and suffering I cause in the world. That's what it means to live according to God's law of love. Though chickens, pigs, cows, and the occasional possum are not as sentient or aware of their mortality as we are, they suffer nonetheless. They know pain, they know fear, and they die just as we do.(Eccles. 1:18-19) I personally prefer not to harm another creature if I don't have to.
And I don't have to. So I don't.
Notice the recurrence of "personally." I'm more than happy to tell people the variety of reasons why I don't chow down on animal flesh. But if you choose not to, I have no right to judge you. God alone judges. That's the whole point Paul's making in Romans.