The second volume of Dumitru Stăniloae's The Experience of God: Orthodox Dogmatic Theology concerns creation and deification. The opening pages begin with a discussion of the function of nature and man's responsibilities towards nature.
This speaks against a kind of platonizing tendency in much contemporary thought -- even in the thinking of persons otherwise self-categorized as naturalists -- according to which human persons somehow stand above and beyond the natural order in various ways. (One example of this would be the attitude of some naturalists or secularists which denies that there are any objective values or disvalues for human beings grounded in human biology, even though this is undoubtedly the case as regards other animals.)
A mistreatment of nature is an obstacle to the deification of the human person because both of them are essentially linked to one another: if man is miserable, then so is nature, and vice versa. Because the misery of nature -- disease, sickness, draught, overfarming, etc. -- means that humanity suffers, Stăniloae rightly infers that the mistreatment of nature implies violence against our fellow man as well: Through the corruption, sterilization, and poisoning of nature, a human being makes his own existence, as well as that of his fellow human beings, impossible. Thus, nature is the condition not just of individual human existence, but also of human solidarity (p. 2). The corollary of this is that a respect for nature implies and facilitates a respect for your brothers and sisters, because they depend on nature for their well-being as much as you do.
Stăniloae emphasizes that a person's attitude towards nature is a marker of spiritual maturity, nearness to God, because nature is a sharer in God's goal of deification. A person who has been brought near to God sees things as God does, and correspondingly will appreciate and care for nature: Nature as a whole is destined for the glory in which men will share in the kingdom of heaven, and even now that glory is felt in the peace and the light that radiate from the person who is a saint (p. 3).
Nature, according to Stăniloae, is a gift of God to humanity. It is a gift which provides humanity with sustenance, a sustenance which naturally renews itself when allowed to function according to its own natural principles: As gift of God, nature renews itself continually in the same propitious manner for human existence, without ever being exhausted in this movement of renewal and fertility (ibid.). But of course, if nature is a gift to humanity, then it is a gift to all of humanity -- as Thomas Aquinas also appreciated -- and so is intended to be a means by which human persons learn to care for one another. The failure to care for nature appropriately implies a deficiency in caring for one's brother and sister:
Thus, when nature is maintained and made use of in conformity with itself, it proves itself a means through which man grows spiritually and brings his good intentions toward himself and his fellow men to bear fruit; but when man sterilizes, poisons, and abuses nature on a monstrous scale, he hampers his own spiritual growth and that of others (ibid.).
When nature is used properly, however, the human persons who through her work upon nature produces a gift for another is actually participating in the primordial gift of nature given to humanity by God: Even with its limited effects, the work man performs on nature in order to make of it in his turn a gift to others recalls the creative act of God whose complete gift is nature (p. 5).
Stăniloae closes by speaking of a new asceticism, which involves the responsible and temperate usage of the goods of nature so that others do not go lacking while we live in excess: Our responsibility toward nature given by God appears today also as a duty to use resources sparingly and not to disfigure nature through pollution. This responsibility protects us from the passions and from seeking any infinite satisfaction in the world (p. 7). As he says, through the temperate use of natural resources, we are shielded from seeking any kind of heaven on earth, so to speak, any kind of satisfaction with life here and now.
Evils perpetrated against nature -- factory farming, for instance -- are obstacles and impediments to the deification of human persons, and so stand squarely opposed to the will of God. The mistreatment and chemical poisoning of the animals leads to unhealthy meat which sickens human persons and other animals who consume it, wholly apart from the gross evil of the farm and slaughterhouse conditions considered in themselves. Stăniloae would urge us to oppose these things in the name of God.