The Second Epistle of Peter was also written by the apostle Peter in the middle of the first century. It warns of false teachers who had come into the Early Church and urges Christians to be brave and patient.

2 Peter 2

2:20 For if after they have escaped the pollutions of the world through the knowledge of the Lord and Saviour Jesus Christ, they are again entangled therein, and overcome, the latter end is worse with them than the beginning.