Book of 2 Peter Summary: Guarding the Truth and Growing in Grace. The Second Epistle of Peter is a sober and urgent letter. It warns against false teachers, reminds believers of the certainty of Christ’s return, and calls them to steadfast growth in holiness. Written as Peter’s farewell message, it carries the weight of a spiritual testament—urging the church to guard the truth, persevere in godliness, and cling to the promises of God.