Any study of a book of the Bible should begin with context. We need to know who wrote it, the person or people it was intended for, what prompted them to write it, and then we need to understand the culture of the time during which it was penned. There are many other factors that help us understand the book better, but those provide the framework for being able to contextualize the words on the pages we will read.
Who Wrote It?
This seems obvious on the surface, especially considering that the first line of Peter's first Epistle is "Peter, an apostle of Jesus Christ." Unfortunately the Bible has not been immune to skepticism, and there are multiple challenges that critics use to attempt to undermine the authority of this book.
- The Final Greetings section says "By Silvanus, a faithful brother as I regard him, I have written briefly to you, exhorting and declaring that this is the true grace of God." - Given that everything we read from the author lines up with Peter, and the opening says it is from Peter, then this is a weak attempt to poke holes in an otherwise solid foundation of truth. Silvanus would have gone by another name, an abbreviated name, like Silas. Now if we back up a few books to Acts we can see that from the day of Pentecost all the way through Acts 15:40 that the names of Paul, Silas, Peter, and others appear countless times. This should be expected since they were traveling companions on the extended missionary journey. This could have just been Silas adding a few words at the end of the letter, or it could be that he was better suited for written communication than Peter, and in turn wrote the letter himself. This was hardly uncommon during the time. This explanation makes sense, and it also resolves the next criticism.
- The Greek is highly advanced, and doesn't fit the image of Peter we are given from the rest of the New Testament record. We know him to be a fisherman, which doesn't exactly make us think of him as a scholar. This makes Silas a good fit for Peter's secretary, which explains both of the first two problems.
- The timeline doesn't match up with what we believe we know about the death of Peter. History records that Peter was martyred in Rome in 64 AD at the hands of Nero, who was one of the most vile Emperors that ever lived. Since the letter opens by addressing those suffering from persecution, and Peter would have died very early on in that process, then it poses a problem for one of the two events. Either Peter didn't die in 64 AD or he didn't write the letter. This historical issue is actually settled by history itself. Along with the torture and murder of an unfathomable number of the early Christians, Nero set out to gather all of the history of the Christian faith and have it destroyed. This included the Gospels, Epistles and all of the records of the people mentioned inside. In 77 AD, he went as far as to burn the entire city of Jerusalem, which he then blamed on the Christian population and set in motion the murder of millions of faithful believers.
Given all of that, it's far more likely that we don't have an accurate record of the death of Peter than it is that this book was written by anyone else. Given the thousands of original manuscripts that survived, it just goes to show how highly circulated these documents were in the first century. Nero used the resources of the entire Roman empire to destroy the record of our faith, and yet he couldn't understand why people were willing to die to preserve them for later generations.
This was obviously an example of God's provision and goes on to further validate the authenticity of Peter's epistles. The early church would have circulated a letter that didn't appear to be from Peter, and they would be in a better position of authority to judge the literary style than people living thousands of years later. The evidence of it's high level of circulation is in the fact that we have these letters at all. Had there not be countless copies being passed from church to church then there wouldn't have been enough to survive Nero's wrath. It seems to me as if each objection answers itself, and that shouldn't be a surprise. If God inspired scripture, then it's hardly a stretch to believe that he also preserved it for all future believers.