Did not Moses give you the law
After Christ had vindicated himself and his doctrine, he proceeds to reprove the Jews for their breaking the law, which contained the will of God: by which it appeared, that they were no proper judges of his doctrine, though they cavilled at it: the question he puts could not be denied by them; for though, properly speaking, God was the lawgiver, yet inasmuch as it was delivered by Moses, it is ascribed to him, and said to come by him; and it was put into his hands, to be delivered by him, peculiarly to the people of Israel; and being given to the Jewish fathers, not only for themselves, but for their posterity in ages to come, is said to be given to the then present generation; and may be understood, either of the whole system of laws, moral, ceremonial, and, judicial, belonging to that people; or else of the particular law, concerning the keeping of the sabbath, which was a peculiar law of Moses, and proper to the children of Israel only:
and [yet] none of you keepeth the law;
though they boasted of it as a singular privilege, and rested in it, and their obedience to it for life and salvation, yet daily broke it in various instances, in thought, word, or deed; yea, those that sat in Moses's chair, and taught it, did not observe and do what they taught; nor could the most holy and righteous man among them perfectly keep it: and many of them, who were most forward to censure others, for the violation of it, paid the least regard to it; and particularly to the law of the sabbath, which both priests and people transgressed, in one point or another, every sabbath day: wherefore our Lord reasons with them,
why go ye about to kill me?
an harmless and innocent man, who never injured you in your persons and properties; and which is a proof of their not keeping that body of laws Moses gave them, since "thou shalt not kill" is one of them: though rather this may refer to the law of the sabbath, and the sense he, that since Moses had given them the law of the sabbath, and they did not keep it themselves, why should they seek to take away his life, for what they pretended was a breach of it? for our Lord here, as appears by what follows, refers to what they sought to do, above a year and a half ago, and still continued to seek after; namely, to kill him, because he had healed a man on the sabbath day, ( John 5:16 John 5:18 ) ( 7:1 ) .