Albert Barnes Commentary Matthew 5:21

"Ye have heard that it was said to them of old time, Thou shalt not kill; and whosoever shall kill shall be in danger of the judgment:" — Matthew 5:21 (ASV)

You have heard. Or, this is the common interpretation among the Jews. Jesus proceeds here to comment on some prevailing opinions among the Jews. His purpose was to show that the righteousness of the scribes and Pharisees was defective and that people needed a better righteousness, or they could not be saved. He shows what he meant by that better righteousness by showing that the common opinions of the scribes were erroneous.

By them of old time. This might be translated, to the ancients, referring to Moses and the prophets. But it is more probable that he here refers to the interpreters of the law and the prophets. Jesus did not set himself against the law of Moses, but against the false and pernicious interpretations of the law prevalent in his time.

You shall not kill. See Exodus 20:13. This literally denotes taking the life of another with malice, or with intention to murder him. The Jews understood it as meaning no more. The comment of our Saviour shows that it was spiritual and was designed to extend to the thoughts and feelings, as well as the external act.

Shall be in danger of. This means one shall be held guilty and be punished by that authority. The law of Moses declared that the murderer should be put to death (Leviticus 24:21; Numbers 35:16). It did not say, however, by whom this should be done, and it was left to the Jews to organize courts to have cognizance of such crimes (Deuteronomy 16:18).

The judgment. This was the tribunal that had cognizance of cases of murder, etc. It was a court that sat in each city or town and commonly consisted of seven members. It was the lowest court among the Jews, and from it an appeal might be taken to the Sanhedrin.