The book of 1st Peter was a series of letters written to all believers in general. The purpose of these letters was to encourage those who were suffering and persecuted to unite and remember why they believed.
In chapters 1-2: Peter explains that in this life we will sometimes suffer or have trials placed before us. He teaches that all Christians are to expect suffering; it is normal for Christians to suffer persecution and even imprisonment and death. Peter explains that we have been given a plan and part of that plan is Salvation, which was made possible by Jesus Christ. He made is POSSIBLE, but not secured. We still have to do our part by working hard to follow in His footsteps… then in the Day of Judgment it will be decided if we did enough to make it back to our Heavenly Father.
In chapters 3-5: Peter explains that part of being a follower is to be ready always to give an answer to those who ask. Therefore, if you believe something to be true and someone asks you the “what?”, or “why?” of your beliefs… you should be ready to give an answer to those who sincerely ask. We should strive to constantly share our beliefs and helps others to learn about Jesus Christ. We should not be surprised when we are faced with trials or heartache, this is all part of the life experience and it is part of being a follower of Christ. Satan is not happy, and knows that as a follower of Christ, we have chosen the correct side. Satan does not want us to be happy, because HE is not happy!