Verse 13 Therefore gird up the loins of your mind, be sober, and rest your hope fully upon the grace that is to be brought to you at the revelation of Jesus Christ; Rest your hope fully upon the grace of Christ.
Wow. If we did that perfectly, we would never have to worry again and we'd always be ready to do His will. He is the only one we can fully rest our hope on-- He is perfect, cannot lie, always fulfills His promises, never makes mistakes, is Holy, just, loving, merciful, all powerful, all knowing, and the list goes on. That who I want to trust fully and rest my hope on!!
Verse 14 as obedient children, not conforming yourselves to the former lusts, as in your ignorance;
This verse is telling us to be obedient and to not do what our lustful flesh wants us to do. We need to learn what God wants and doesn't want us to do so that we will not remain ignorant.
Verses 15 and 16 but as He who called you is holy, you also be holy in all your conduct, 16 because it is written, “Be holy, for I am holy."
He is holy-- and we are to be like Him. So we must be holy. What does it mean to be holy? It means to be set apart, called out, separate, pure, different, set apart, perfect.We are called to be like Christ, and therefore, different from the world. We should stand out-- in our words, our actions, how we treat our family, how we dress, and so on. As Christians, we must be holy, different from the world around us.
These are some thoughts I had on these verses in 1 Peter for a "study" I was doing with someone else. I haven't done any more yet, though. :( )