This section of Peter’s epistle is predicated on what he discussed before. They were begotten by God to a “living hope” (v. 3). They had a promise of an inheritance (v. 4-5). Their faith, being tested, was found genuine, and the end thereof is the “salvation of [their] souls” (v. 9). This is that which was prophesied about, and what the prophets desired to come to know fully, as well as angels, but was not for them, rather, for those to whom Peter was writing (v. 10-12). For this reason, given the hope of such glory and salvation, they were to act appropriately.

“Gird up the loins of your mind” – Before going to work, workers would tuck their free flowing garments so as to allow their limbs free course, rather than being impeded. It was a matter of decisive action to efficiently accomplish what work they set out to do. The Christian cannot have his mind “free-flowing,” but must be focused, not allowing his thoughts to wonder aimlessly.

“Be sober” – Sobriety is most often referred to as being free from intoxicants. Such intoxicants lower inhibitions, thus destroying focus, and temperance. A Christian must not let the lusts of the world cloud his vision, and impair his spiritual focus. He must be temperate.

The Christian must be focused on the goal ahead. As such, he is continually submitting to God in obedience, and denying self, for that is what allowed him to access such hope by grace in the first place. This requires a standard to live by. Someone to conform to. It is natural that we should conform to “He who called [us].” Because He is holy, we must be holy. This leaves no room for moral laxity, rather, we must be completely set apart from the world, and dedicated to His service (cf. Romans 12:1-2).