The Apostle Peter starts 2 Peter 3 by using the term “beloved” (verse 1) to address his audience. In doing so, Peter indicates that he intends his words for those who, like himself, have dedicated, or consecrated, their lives to God. Continuing through verse 1 and into verse 2, Peter announces that the theme of his upcoming address is an encouragement to remain faithful to one’s vows of consecration.
One difficulty Peter particularly focuses on is time; specifically, the perceived “long” amount of time that it will take for Jesus’ second presence to be understood by the world (verse 4). Verses 4-7 are a reminder that throughout history, mankind has had difficulty understanding God’s plan and remaining faithful to Him due, at least in part to the perceived lengthy time frames involved in His plan’s execution. To underscore the difference between God’s scale and man’s scale, he equates “a day with the Lord” to “a thousand years” as mankind reckons time (verse 8). He addresses these words, again, to his “beloved,” his brethren in Christ, emphasizing that the world in general will not understand or accept this difference of scale.
Starting in verse 9, Peter begins to more specifically address the time of Jesus’ second presence. In verses 9-14, he reminds his brethren that due to its nature, Christ’s second presence will not be recognized by the world in general (“the day of the Lord will have come as a thief” – verse 10) and that it will be accompanied by a complete dissolution of mankind’s governing and religious systems (“seeing that these things [mankind’s systems, including all the priorities and pursuits of the world] are thus all to be dissolved” – verse 11). He then emphasizes the need to stay faithful to one’s consecration vows, because understanding God’s plan, even when one doesn’t fully understand the time frames involved, brings a unique perspective and a corresponding responsibility. Jesus taught his followers to set aside the pursuits of this world and set one’s heart and hopes upon God and His kingdom (Matthew 6:19-21). This condition of heart and mind can be difficult to maintain over time, but those who seek to please God are still responsible for doing so.
Peter begins to conclude his thoughts starting in verse 15, where he reminds his brethren that the Apostle Paul also exhorted them to remember many of the same lessons as Peter was currently expressing. For example, in Philippians 3:13-14, Paul explained how he had forgotten the pursuits of the present world as “things left behind” and focused on his consecrated service to God as “the one thing he did,” devoting all his effort to “looking forward” to the fulfillment of God’s plan. Paul also taught the eventual tearing down of mankind systems, to be replaced by Christ’s rulership, such as in Hebrews 1:19-22.
2 Peter 3:16 begins with Peter reminding his brethren most of the world wouldn’t understand Paul’s writings, just as they wouldn’t understand Peter’s (“some things hard to be understood”). Because the lessons were meant for God’s followers, and not the world in general, the latter would struggle to understand them (“the ignorant [those of the world who don’t know or understand God or Jesus] and unsteadfast [those who only have a surface level relationship with God and Jesus, but don’t make the effort to fully devote their lives to God] wrest [unsuccessfully struggle to understand]”. He reminds his brethren that, throughout history, those ignorant of God or unfaithful to Him have always been unable to fully understand any of the scriptures, not just Paul or Peter’s writings (“as they do also the other scriptures”). Eventually, all mankind will be given the opportunity to fully understand God’s plan for them, and at that time, gain an insight into the Bible that they didn’t, or even couldn’t, have earlier. Peter ends the verse with a reminder that with knowledge of God’s plan, either now or in the future, carries a responsibility to fully devote one’s heart and mind to God. Failing to do so puts one at risk for ultimate destruction (“unto their own destruction”).
Peter concludes his thoughts in verses 17-18, where he repeats the main message of his writing. He again encourages his brethren to remain faithful to their vows of consecration to God. He reminds them that many of the truths of God’s plan have been revealed to them; that they were able to understand the messages that he and Paul delivered to them. It was, and still is, up to every faithful follower of God to remain faithful to that “one thing they do” and not become “carried away with the error of the wicked.”