Expositor's Bible Commentary 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)

Jesus’ contemporaries had heard that the law given their ancestors forbade murder and that the murderer must be brought to “judgment.” But Jesus insists—the “I” is emphatic in each of the six antitheses—that the law really points to his own teaching: the root of murder is anger, and anger is murderous in principle. One has not conformed to the better righteousness of the kingdom simply by refraining from homicide. The angry person will be subject to God’s “judgment” (GK 3213; for no human court tries cases of inner anger). To stoop to insult exposes one not merely to (God’s) council but to the “fire of hell” (on this expression, see comment on Mk 9:43–48).

“Brother” (GK 81) cannot in this case be limited to male siblings but to one’s fellow believers. The Christian habit of calling one another “brother” and “sister” goes back to Jesus’ instruction as part and parcel of his training them to address God as Father (6:9). Among Christians anger must be eliminated.