Musar su Deuteronomio 14:21

“You shall not eat any corpse” (Deuteronomy 14:21). Our Rabbis, may their memory be blessed, said (Chullin 32a), “Anything that is disqualified during slaughter is a corpse (neveilah).” And it is goodly for the reprimanders to warn the people, so that they should be careful about the law of slaughtering and all of its details, to fulfill its dictates. And for all of its laws, they should choose a slaughterer (schochet) who fears sin, since a large number of Israelites are dependent upon him for the [proper execution] of the commandments of slaughter and examination. And though it is true that our Rabbis, may their memory be blessed, said (Chullin 3b), “Most of those found around slaughter are experts” - there are places without concern and without reprimand. There, most of the people found around slaughter are not understanding experts. And we have also seen scandal in some of them. For many of the experts have distanced themselves [from these places] out of fear of sin; and the heart of those that do not not fear, does not understand how to be exacting in the examination of the knife. For one has to focus his heart very, very much in its examination. Do you not see that a man may check two or three times and not feel a small nick (that would render the knife improper), but find it afterwards when he set his heart to it in the end? So [this shows] that the sense of touch is according to the focus of the heart. [This is] besides that a man that has no fear will err in the examination of the marks and the rest of the ways and angles that are clearly revealed to anyone who knows the doctrine and the law.