The apostle Peter encouraged his Christian readers who were engaged on two different battle fronts (1Pet 2:11-12). One battle is raging inside the Christian himself while the other battle he experiences in the culture where he lives as an alien or stranger.
With respect to the first conflict, Peter urges his readers, those beloved by God, to abstain from fleshly lusts which war against the soul. There is a war within the Christian! The desires of the flesh or sinful nature are at odds with the new desires given to the Christian by the indwelling Holy Spirit. Paul wrote in Galatians 5:17, “For the sinful nature desires what is contrary to the Spirit, and the Spirit what is contrary to the sinful nature. They are in conflict with each other, so that you do not do what you want.”
The second conflict is experienced by the Christian in the world at large. Jesus Himself said that His followers are in the world, but not of the world. In fact, He indicated that because the world hated Him, it will also hate His followers. This hate is expressed, according to Peter, when they speak of us as evildoers. Because the world may falsely accuse Christians of wrongdoing, Peter urges them to live honorably among their opponents. Perhaps, those who observe the good works performed by Christians will in the end glorify God!
In summary Peter says, “We must abstain from sinful lusts while maintaining a godly lifestyle in this world.”