Here Peter is warning of false teachers and their corrupt doctrines. Peter was especially cautioning fellow Christians against two popular philosophies that were circulating… Gnostics and Antinomians. Gnostics taught that in addition to believing in Christ, you must also receive esoteric knowledge. While Antinomians believed that since salvation was by grace alone, all requirements to keep moral law were irrelevant and unnecessary. Peter refuted both philosophies to cheapening God’s gift of grace and eviscerating the power of the Cross and the blood of Jesus…instead, reminding the Church to stick to the foundational Truths they had been taught and read in the Scriptures…all the while being given Spiritual insight by the Holy Spirit. Times change and so do popular philosophies that waft in and out of Churches…and we must all be on guard for corrupt and deceptive doctrines that could cause us to run aground.