Deuteronomy 25
[4] Thou shalt not muzzle the ox when he treadeth out the corn.
1 Corinthians 9
[9] For it is written in the law of Moses, thou shalt not muzzle the mouth of the ox that treadeth out the corn. Doth God take care for oxen?
[10] Or saith he it altogether for our sakes? For our sakes, no doubt, this is written: that he that ploweth should plow in hope; and that he that thresheth in hope should be partaker of his hope.
1 Timothy 5
[18] For the scripture saith, thou shalt not muzzle the ox that treadeth out the corn. And, The labourer is worthy of his reward.
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The Torah is filled with mitzvot relating to animal welfare. It is forbidden to prevent an animal from eating from produce upon which it is working, such as threshing grain or carrying a bundle of hay.
– Tom Irvine