In this book I love that Peter really expresses that we have everything we need to be successful in this walk. That the word of God is not just a story but truth and the exact instruction we need. He even makes it clear that there will be people and even ourselves that can be turned to go back the other way ,believe false teaching but it is important that we as individuals Know are word refresh our minds with it daily and obey what we learn.
In the book of Jude The fact that he again reminds us that we need to be aware of false teaching. That we know the truth of what Jesus did for us at the cross yet we can be swayed by what we hear from the world. That we need to be prepared for these things by knowing the word of God and standing firm on it no matter what.