Prov 12:10

“"The righteous has pity upon the soul of his animals." It is an exercise of human charity when someone, by means of his animals, becomes accustomed to show mercy upon his fellow human beings. Indeed he who has pity upon animals tends to have much more pity upon his brothers.… Do the righteous have pity upon the souls of their animals? Absolutely. Certainly it is necessary to convey benevolence toward them, so that there may be a greater exercise [of benevolence] toward fellow human beings. Indeed with good reason God ordered that we carry hurt animals and take back those that stray, and not to bind the mouth of an ox. He absolutely wants us to preserve the health of animals: in the first place for our sake, second, in order that they may provide us with their menial service. At the same time it is an exercise of benevolence and care. Indeed the one who has pity upon strangers has much more pity upon those who are familiar to him. And the one who has pity upon his servants has much more pity for his brothers. But you may say: an animal provides you with a profitable service, but with what does a brother provide you? He is helpful to you, I say, much more from the viewpoint of God. You can see that when we offer care such as we do for our animals we do not consider this demeaning. For, in doing so we are not only serving them but also ourselves.”