In verses 12 through 15, Peter states the big purpose of why he’s writing this letter: he wants this church to remember and put into practice what he’s told them. It’s important for us to know that even though this church was doing well, Peter felt very strongly that they consistently needed to be reminded of the truths they already know. For many of us, our greatest need is not to know more truth but to know how to apply the truth we already know.