פּירוש אויף שמות 22:4

כי יבער … בעירה ובער All these terms are connected with the word בעיר which signifies “cattle”, as in (Numbers 20:4) אנחנו ובעירנו “we and our cattle" .

כי יבער איש שדה או חרם, “when a man lets his livestock loose to graze in someone else’s field or vineyard;” the expression בער always describes destruction of something, as in Deuteronomy 21,9: ואתה תבער דם הנקי, “you must out eliminate innocently spilled blood;” [we are more familiar with the expression from getting rid of our chametz on the eve of Passover. The author quotes two more examples, which I omitted. Ed.]

כי יבער איש שדה או כרם, within his own property, (originally)

כי יבער means accordingly, he takes his cattle into the field or the vineyard of his fellow-man and causes damage to him by one of these two ways: either by the mere fact that he lets his cattle go (tread) there (ושלח את בעירו), or by letting it graze there (ובער). Our Rabbis explained (Bava Kamma 2b), that ושלח refers to the damage done by “treading” (Rashi uses a Biblical phrase Deuteronomy 5:1. “treading of the hollow of the foot”) and ובער to the damage caused by the tooth that eats up and removes (מבערת) the crops (grazing).