Recently, someone who noted that I am a vegetarian asked, "If animals weren't created to eat, what were they created for? I thought we were to have dominion over them."
It is indeed true that in Genesis 1.26 God says humanity is to have dominion over the animal kingdom. The word dominion means literally to subjugate and to prevail over another, and we have used this permission by God to upset, rather badly, the delicate balance of the natural world by animal over hunting, by domesticating for slaughter, and by the elimination of natural predators. Note that in Genesis 1.29, only three verses later, God tells the humans what they may eat: "God said, 'See, I have given you every plant yielding seed that is upon the face of all the earth, and every tree with seed in its fruit; you shall have them for food.'" Notice there is no mention of killing or eating the animals, only in having dominion over them.
We get a clearer understanding of the divine place of animals when we read the second creation story in Genesis 2. Here the human is created and God decides it shouldn't be alone. "Then the Lord God said, 'It is not good that the human should be alone; I will make a helper as a partner'" (Genesis 2:18). So God creates the animals and brings them one by one to the human for naming and to see which will be a suitable "partner." The word partner here, by the way, is the same one used when Eve is finally created. It means literally helper, mate, and/or companion. In any case, like today, the human rejects the animals created by God as somehow inferior, relegating them instead to a state of "dominion" rather than elevating them to "partners" as God apparently intended.
From the beginning, it seems, God's intention was for there to be some symbiotic relationship between all creation. Animals were apparently intended, not for consumption, but for companionship and, according to the first creation account, to be helpers or even servants to meet our needs--but not to be consumables. Certainly from these creation accounts we can legitimize the partnership of animals as providers of milk and perhaps even eggs. We can justify the use of animals for wool and as beasts of burden. But in no way can we construe the creative purpose of animals as food.
The use of animals for food does not receive divine sanction or permission until after Noah climbs out from the ark and releases the animals. At that moment God pronounces that the animals shall naturally be fearful of humanity and then and only then does God allow the use of animals for food--and the tone of the passage is one of resignation and frustration, as if God was giving in to some custom already in wide-spread use.
However, in the pictures and visions of the coming of paradise, it is clear that one day the animal world will live in harmony with humanity and with itself. Isaiah writes, "The wolf shall live with the lamb, the leopard shall lie down with the kid, the calf and the lion and the fatling together, and a little child shall lead them. The cow and the bear shall graze, their young shall lie down together; and the lion shall eat straw like the ox. The nursing child shall play over the hole of the asp, and the weaned child shall put its hand on the adder's den" (11.6-8).
The ideal throughout the bible, from creation until the time of paradise, is that animals and humans get along with each other and do not eat each other, choosing instead to live in balance and in symbiotic harmony. This then is the divine purpose of the animals upon the earth, and why I choose not to eat them.