The Buddha in the Surangama Sutra: “Bhikshus who do not wear silk, leather boots, furs, or down from this country, or consume milk, cream, or butter can truly transcend this world. When they have paid back their past debts, they will not have to re-enter the triple realm. Why? It is because when one wears something taken from a living creature, one creates conditions with it, just as when people eat the hundred grains, their feet cannot leave the earth. Both physically and mentally one must avoid the bodies and the by-products of living beings, by neither wearing them nor eating them. I say that such people have true liberation.” – http://www.cttbusa.org/shurangama6/shurangama6_2.asp
Comments: The gise of the above passage, though it does not mention wool, is that animal exploitation should not be supported (especially on the Bodhisattva path of safeguarding beings from harm). Notice that milk, cream and butter does not require killing to be derived too – just like wool – but there is still exploitation involved – before killing. While deriving wool (e.g. for lanolin) does not require killing, it is continual exploitation – up till the moment they get killed for meat. There is no happy retirement. Being de-wooled annually is just part of the process that leads them to the slaughter… to ‘milk’ them for all they are worth till they are ‘worthless’.
Some might rationalise that wool has to be sheared before it gets so long that it makes sheep too hot for summer conditions. But this is untrue as they will shed by themselves to suit weather conditions, while humans steal it in bulk too much and too fast. Even if this is true, before humans began trapping and domesticating animals (which is against a Bodhisattva precept), how did the sheep deal with ‘being too hot’? How would any sheep like being naked without their wool? It is an unnatural and even cold state that must trouble them them to some extent. Just like most humans don’t like to be shaved bald, why torment sheep by forcing them to endure what they do not want? The truth is, like honey, wool is not an innocent product. Some sheep do suffer (e.g. by fleece rot and flystrike) and die when their wool is stolen. For the hard facts on wool, please see http://www.veganviews.org.uk/vv77/vv77wool.html
羊毛张在羊身上，
何必带在人身上？ － 石子Since wool grows on sheep’s bodies [for them],
why should it be worn on human bodies [for us]? – Stonepeace