Jesus told us that, if someone struck us on our right cheek, we should then offer the other (Matthew 5:39). Isn’t that inviting persecution? Not really! It no more invites persecution than saying: “Don’t kill Bill” invites someone to kill Bill. All Jesus meant was, if what we do for him causes some to treat us unjustly, don’t cease from doing the good, simply because some are opposed to what we say and do. Jesus simply meant that we should be ready to receive insults in order to spread the Gospel. As Peter writes to believers in Asia Minor, it seems the persecution being conducted there revolved around malicious slander (1Peter 2:12; 3:10, 16). The unbelieving Jews seemed to be trying to get followers of Jesus into trouble with the gentile authorities (cf. Acts 13:50; 14:2; 17:5-9; 18:12-13).
Nevertheless, from time to time Christians deliberately place themselves in harm’s way (1Peter 3:14). Why do we do that? It is because Christ suffered unjustly (1Peter 3:18) and left us an example to follow (cf. 1Peter 2:21-24). Jesus suffered unjustly at the hands of unlawful men, therefore, requiring a reward from God (resurrection). That is, if what Jesus said is true, namely, that, instead of receiving good for doing good, one suffers for righteousness sake, God will reward that one in his Kingdom (Matthew 5:10; cf. 1Peter 3:9, 14). In other words kind produces kind (cf. Genesis 1:11-12, 21, 24-25). If what man does rejects this law, God will correct the evil man has done. Therefore, Jesus had to be resurrected in order that God’s integrity remain intact. According to Peter, we, too, are called to suffer unjustly from time to time at the hands of the unjust, so that we also might inherit a blessing or reward in the Kingdom of God. This is not eternal life, for that has been secured for us by Jesus’ righteousness. Nevertheless, our righteous acts, unrewarded here, must be rewarded later by God, if his truth, kind produces kind, has any meaning.
Peter tells us that Christ suffered for the unrighteous in order that we could be brought to God—to bring us to repentance, thus ending our rebellion against him. Christ was put to death in the flesh but quickened in the Spirit (1Peter 3:18d). What this means, as far as unrighteousness is concerned, is that what Christ has done is repeated in the believer. The word was made flesh (Jesus—John 1:14), but was crucified and was raised to a new, different life. So it is with us as we crucify or put our flesh to death by abandoning our former life, in order to live out the Spirit of Christ dwelling in us (cf. Romans 6:6; Galatians 2:20; 5:24). We live, but our life is in him—in his resurrection. The world with all of its goals and pleasures is dead, as far as we are concerned. In other words, we have new goals and delights, which the world considers a waste of time and effort—death, as far as they’re concerned (Galatians 6:14; 1Corinthians 1:23; 2Corinthians 2:16).
Peter takes another page out of history by mentioning Noah as an example for believers of Peter’s day. In his second epistle he says that Noah was a preacher of righteousness (2Peter 2:5). What Peter means to say is that, before he took on flesh, the Spirit of Christ testified to the antediluvian age through the preaching of Noah, the servant of God. This should be an encouragement to Peter’s readers, because it is implied by the effectiveness of Noah’s preaching (1Peter 3:20), that he was ridiculed for building such a large vessel, for salvation in the event of a global flood, something believers are ridiculed for even today! If the Spirit of Christ spoke through Noah, and he was persecuted for his preaching, why would it be so unbelievable in the first century AD, that believers in Christ would be similarly ridiculed and slandered (1Peter 3:19-20)?
Peter concludes his thought in 1Peter 3:21 by telling his readers that Noah and his family were saved by placing themselves in the ark, which was not affected by the judgment of God (i.e. death). In the same way the disciples of Jesus are placed in him – the Ark of the Covenant – and we are not affected by death, the judgment of God, which was soon to come upon the Jews who slandered the Gospel (cf. Hebrews 9:27; Romans 8:1). The fact that Jesus was raised from the dead by God shows that he is the Messiah (cf. Acts 13:33), and, if he is the Messiah, then he reigns today from the right hand of God (1Peter 3:22; cf. Psalm 110:1). In other words, all power in heaven and in earth is given to Jesus, the Messiah or Christ (Matthew 28:18). Peter mentions that angels (messengers of the Gospel), authorities (world leaders and all lesser offices of authority that serve them) and powers( the military might of the world) are subject to and serve Jesus. If this is so, believers should understand that nothing can touch us without it being within the will of God. No one can hurt us, unless it is allowed by God, and in such a case that would serve a greater good.
 Since most people are right handed, in order for a right handed person to strike another on the right cheek with his right hand, he would have to use the back of his right hand. This amounts to an insult, not a death threat.