א֣וֹ בְאֵיבָ֞ה הִכָּ֤הוּ בְיָדוֹ֙ וַיָּמֹ֔ת מֽוֹת־יוּמַ֥ת הַמַּכֶּ֖ה רֹצֵ֣חַֽ ה֑וּא גֹּאֵ֣ל הַדָּ֗ם יָמִ֛ית אֶת־הָרֹצֵ֖חַ בְּפִגְעוֹ־בֽוֹ׃
אָדער ער האָט אים מיט פֿײַנטשאַפֿט געשלאָגן מיט זײַן האַנט, און ער איז געשטאָרבן, זאָל טײטן געטײט װערן דער שלעגער; אַ מערדער איז ער; דער בלוטמאָנער זאָל טײטן דעם מערדער, װען ער טרעפֿט אים.
Rashi
וגם בעליו יומת AND HIS OWNER ALSO SHALL BE PUT TO DEATH by a visitation of God. You might perhaps think he shall be punished by human agency (the judges)! Scripture, however, states, (Numbers 35:21) “he that smote him (a human being) shall surely be put to death; for he is a murderer” — the force of these last words is to intimate that for a murder committed by himself you shall put him to death (i. e. he suffers death by human agency as is the law regarding a murderer), but you shall not put him to death on account of a murder committed by his ox; this must be left to God (Sanhedrin 15b; cf. also Mekhilta).