1. He declared in His Sermon on the Mount, “Ye have heard that it hath been said, An eye for an eye, and a tooth for a tooth: But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also” (Matthew 5: 38–39). Thus, the law of an “eye for an eye” was primarily a social law that was modified by Jesus and was not a timeless spiritual principle.
2. Indeed, anyone who violates the Sabbath “shall surely be put to death” (Exodus 31: 14). However, Jesus performed acts of healing and charity on the Sabbath. The Gospel of John relates, “And therefore did the Jews persecute Jesus, and sought to slay him, because he had done these things on the sabbath day. But Jesus answered them, My Father worketh hitherto, and I work” (John 5: 16–17). Likewise Jesus said, “The sabbath was made for man, and not man for the sabbath: Therefore the Son of man is Lord also of the sabbath” (Mark 2: 27–28).
“Jesus’ attitude toward the Sabbath, coupled with the tradition that his resurrection occurred on the first day of the week (Sunday; cf. Matt. 28: 1), meant that Sunday rather than the Sabbath (Saturday) became the chief liturgical day for Christians.”
(Meeks, ed., The HarperCollins Study Bible, p. 1878; “Sabbath,” in Achtemeier, ed., The HarperCollins Bible Dictionary, p. 955.)
3. Jesus also altered the Jewish law of divorce. In the Old Testament, Moses said, “When a man hath taken a wife, and married her, and it come to pass that she find no favour in his eyes, because he hath found some uncleanness in her; then let him write her a bill of divorcement, and give it in her hand, and send her out of his house” (Deuteronomy 24: 1). But Jesus said, “Moses because of the hardness of your hearts suffered you to put away your wives: but from the beginning it was not so. And I say unto you, Whosoever shall put away his wife, except it be for fornication, and shall marry another, committeth adultery: and whoso marrieth her which is put away doth commit adultery” (Matthew 19: 8–9).
Advancement is not always measured quantitatively but also qualitatively. Christ brought a better quality of life and a more humane lifestyle.