"The first chapter vividly portrays the nature of the Christian life with its challenge to spiritual growth and maturity, built on a sure foundation. The second part of the epistle is a ringing polemic against the false teachers who would allure and seek to mislead God"s people, while the third chapter deals with the heretical denial of the return of Christ and concludes with some fitting exhortation to the readers." [1][source]
Second Peter is one of the few New Testament epistles in which chapter divisions consistently coincide with thought divisions. [source][source][source]
"In seeking to prepare the readers against the danger from the false teachers, Peter states in chapter1that their safety lies in their clear apprehension of the nature of the new life in Christ and their spiritual growth and maturity in the faith as the best antidote against error." [2][source]