Although the Old Law's teaching on this subject was clear, Jesus had a new revelation to share. He declared in Matthew 5:39-41 - "But I tell you not to resist an evil person. But whoever slaps you on your right cheek, turn the other to him also. If anyone wants to sue you and take away your tunic, let him have your cloak also. And whoever compels you to go one mile, go with him two."
First, Jesus shares an example of non-resistance to personal insults. Rather than resist an insult (such as a facial slap), we should meekly endure it and suffer another rather than resist evil with evil (cf. Prov. 15:1).
Second, we see an example of non-resistance to judicial injustice. Disciples need to remember that physical things such as clothing are replaceable (and truly insignificant in the big picture). Wasting precious time fighting over matters such as these is not helpful for the follower of Christ; rather, it is a hindrance.
Third, Jesus gives an example of non-resistance to government oppression. In that day, the Roman soldiers had the authority to require a person to carry his baggage or armor one mile (cf. Luke 23:26). The Jews had mile markers along the roadsides, and they would typically drop the baggage after the first mile. Jesus commands a willingness to go two miles! Imagine the soldier's surprise! The individual is obviously not thinking about his "rights." He is not harboring hateful thoughts toward the soldier for "making" him carry the soldier's load. He is willing to cheerfully comply and serve. The meaning for us is that we should perform beyond the call of duty; we should do more than what is expected. Truly, love begins where duty ends.
Jesus then states - "Give to him who asks you, and from him who wants to borrow from you do not turn away" (Matt. 5:42). If one is in need and asks for help, we should not refuse to give what we can.
Jesus' words in this section are perhaps best understood as general principles of non-resistance and not as absolute commands to always be applied literally (just as 5:29,30 are not to be applied literally). After all, did the Lord really intend that evil doers be free to slap or insult us over and over again? Are we always to give to those who ask of us, turning no one away? The answer is no (cf. John 18:20-23; II Thess. 3:10). Jesus' point is that small injuries or offenses are to be gracefully passed over. If someone slaps you, you've been insulted, but it's not an assault on your life. You should not feel humiliated but should rejoice in the opportunity to return good for evil (assuming that you didn't deserve the slap). To let someone have your coat or other possession or to go with them two miles is to show in attitude, word, and deed that you are not filled with covetousness or hatred but with a spirit of love. This is the type of righteousness Christ expects of His disciples (cf. Rom. 12:17-21). This type of response will have the best chance of touching the hearts of others for the Lord.
Friends, this world is filled with injustices. Followers of Christ will be wronged in many ways, but there will be a day of final judgment. Our brief time spent here must be used to glorify the Father through good works (cf. 5:16). To insist on every individual right or to retaliate against every personal injury is to dispute continually with all men. Such actions describe one filled with selfish pride, not humility (cf. 5:3,5). This type of response glorifies Satan, not God! However, be careful not to misapply this passage. Jesus never said not to restrain the murderer's hand. He never said not to oppose the wicked tyrant. And, He never intended for our behavior to encourage greed or laziness in others.