Matthew 5:21

Ye have heard. Jesus gives specific examples of His law interpretation. As Author, He is the only true expositor. He removes rabbinical casuistry, restoring truth’s beauty.

“Ye have heard” implies most in the audience had not read the law themselves, expected as they were peasants and fishermen (MB 39). Later, Jesus asked priests and elders, “Did ye never read in the scriptures?” (Matt. 21:42). A group in the Temple said, “We have heard out of the law” (John 12:34).

It was said. Rabbis introduced their remarks with these words, also used to cite Scriptures.

By them of old time. Or “to them of old time,” meaning “to the ancients.”

Thou shalt not kill. The sixth commandment (Ex. 20:13).

In danger of the judgment. Liable to prosecution. Manslaughter was distinguished from murder, with protection for the slayer (Num. 35:6; Deut. 19:3). Reference is to intentional shedding of blood and legal punishment.