Mary Schertz points out in an article in Word & World that 1 Peter is structured around a central chiasm in 2:11-3:12. At the center is a hymn, celebrating the cross of Jesus, but on either side are words to slaves and wives. Schertz points out that “these slaves and wives were given the highest moral authority (after Jesus) in the internal life of the believing communities.” Those with the least protections, those most vulnerable to mistreatment and abuse are singled out by the apostle because they, like Christ, must commit themselves to Him who judges righteously (2:23).
With Christ at the center, explicitly labeled our “example,” wives of unbelieving husbands and slaves of harsh masters are encouraged in faithfulness but also pointed out as examples for the Christian community. If we want to see examples of faithfulness we have to look to the weak, to the vulnerable, to the unprotected who commit themselves to the Judge who judges righteously.