to butcher: to kill an animal and cut it up for eating, and so to cut people down like meat animals
This is the butcher's word, not the priest's. It covers the whole practical business of killing an animal and dressing it so people can eat: the steward told to kill something for Joseph's guests, Nabal boasting about the meat he had prepared for his shearers, Wisdom laying out her banquet. Hebrew has other verbs for the killing that happens at an altar, one for cutting the throat of a sacrifice (שָׁחַט) and one for offering it up (זָבַח). This word is neither of those. It points toward a kitchen and a table.
Turning a butcher's word on human beings is therefore a deliberate shock. When the wicked bend the bow to cut down honest people, when a poet says God killed without pity, or when a prophet describes a sword sharpened and ready for the work, the victims are being pictured as livestock: handled, helpless, and brought to the block. Nothing in the word softens that. It is the sound of a knife, not the language of a sentence handed down in court.
The best known use is a comparison. Jeremiah says he was like a tame lamb led out to be killed, trusting the hands that led him and never guessing what had been planned. The same picture is later turned on Babylon, brought down like lambs and rams and goats. In both places the force of the image comes from how unremarkable the action is. Nobody grieves for the lamb.