It’s an endlessly fascinating epistle, even mind-blowing at times. If you haven’t read it lately, do so!
Nelson Kloosterman has an interesting discussion of one aspect of 1 Peter, life in a pagan culture: what if we are alien-residents, rather than resident-aliens? What if “pilgrim” vs. “participant” is a false dichotomy? Here is his money shot: “Pilgrimage is not the alternative to cultural participation. Pilgrimage is the manner of Christian cultural participation.”
For my part I’ve been working through what 1 Peter teaches on missional suffering (as opposed to generic suffering of the sort all humans experience) and the death of Jesus.
Dan McCartney observes, “There are few books in the New Testament more intensely concerned with the atonement than 1 Peter. Yet the comments in this letter on the redemptive work of Christ in his suffering and death all take place in the context of ethical discussions about the behavior of servants, or the Christian response to undeserved suffering, or general exhortations regarding the Christian life.”
For 1 Peter as for the gospels and the rest of the NT, the death of Jesus is not about doctrine alone. It is a picture held up for readers to imitate in various ways, a picture of a life lived in submission to God in a broken world. “The Messiah suffered for you, leaving you an example, that you should follow in his steps” (1 Pet 2:21).
The term Peter uses for example, hypogrammos, can refer to an alphabet, often engraved in a plate, a standard provided to students to use when learning to write letters. Karen Jobes notes the inability of English terms to convey this sense: “‘[E]xample,’ ‘model,’ or ‘copy’ are too weak, for Jesus’ suffering is not simply an example or pattern or model, as if one of many; he is the paradigm by which Christians write large the letters of his gospel in their heart.”
Jobes concludes: “This is a strong image associating the Christian’s life with the life of Christ. For one cannot step into the footsteps of Jesus and head off in any other direction than the direction he took, and his footsteps lead to the cross, through the grave, and onward to glory.”
 Dan G. McCartney, “Atonement in James, Peter and Jude: ‘Because Christ Suffered for You,’” in The Glory of the Atonement, 180. Note the subtitle of Edmund Clowney’s exposition of 1 Peter: The Message of 1 Peter: The Way of the Cross (The Bible Speaks Today; Downers Grove, Ill.: InterVarsity, 1989); Karen Jobes, 1 Peter (BECNT), 195.