When looked at in this way, it is clear that different things are being discussed.
An alleged contradiction is said to occur between 2 Corinthians 1:131 and 2 Peter 3:16. One passage states that what was written could be understood, and the other states that there are things which are hard to understand. Is this an irreconcilable contradiction? The easiest way to demonstrate that there is no contradiction is to examine the extended context of both passages. When looked at in this way, it is clear that different things are being discussed.
For our boasting is this: the testimony of our conscience that we conducted ourselves in the world in simplicity and godly sincerity, not with fleshly wisdom but by the grace of God, and more abundantly toward you. For we are not writing any other things to you than what you read or understand. Now I trust you will understand, even to the end (as also you have understood us in part), that we are your boast as you also are ours, in the day of the Lord Jesus (2 Corinthians 1:12–14).
And consider that the longsuffering of our Lord is salvation — as also our beloved brother Paul, according to the wisdom given to him, has written to you, as also in all his epistles, speaking in them of these things, in which are some things hard to understand, which untaught and unstable people twist to their own destruction, as they do also the rest of the Scriptures (2 Peter 3:15–16).
In the 2 Corinthians passage, Paul is writing to people he knew and loved (2 Corinthians 2:4) and who loved him (2 Corinthians 8:7) and also knew how he conducted himself when he was with them in person. They also had received at least two letters from Paul, so they also knew and could recall what he had said to them before. They read and understood that Paul was talking to them based on the way he and the other members of Paul’s missionary team had conducted themselves when they were there. They had read and understood most of what Paul had written to them in 1 Corinthians (though 2 Corinthians 1:14 mentions that they may not have grasped everything fully) because, even though they had some sin problems, they were a Christian church and the members were indwelt by the Spirit (Romans 5:5; 2 Timothy 1:14; Titus 3:4-6) and seeking to follow Christ. As believers, those in the Corinthian church had the benefit of the Holy Spirit, who helps believers understand the Scriptures and spiritual matters (John 14:26; John 16:13; Romans 8:26–27; 1 Corinthians 2:11–14).
Peter’s Written Warning
In 2 Peter 3 (beginning in verse 3), Peter is addressing the church and telling them of false prophets and scoffers, critics of Scripture who would not be able to understand Paul’s writings or would deliberately twist them so that they could deceive others into following a false gospel. Peter, while admitting that some of Paul’s epistles were hard to understand (meaning that they had to be carefully read) is not saying that everyone twisted Paul’s words—only those who are untaught and unstable. In other words, those who were blinded by sin and Satan. Peter then contrasts those people with the true Christians in the churches in Asia he was writing this warning to:
You therefore, beloved, since you know this beforehand, beware lest you also fall from your own steadfastness, being led away with the error of the wicked; but grow in the grace and knowledge of our Lord and Savior Jesus Christ. To Him be the glory both now and forever. Amen (2 Peter 3:17–18).
Paul was writing to Christians while Peter was warning about false prophets: two totally different circumstances.
There are no contradictions here, just different groups of people being addressed. Paul was writing to Christians while Peter was warning about false prophets: two totally different circumstances. Those who were false prophets and those who would deliberately twist Scripture to their own ends did not have the Holy Spirit dwelling in them to illuminate Scripture (Romans 8:9; 1 Corinthians 2:14; Jude 1:19). Yes, Paul’s Epistles contain some profound theology and some things that are hard to understand, yet the key word here is some. Peter did not say all of Paul’s writing was hard to understand, and the readers in Corinth knew Paul quite well and could, in most cases, easily understand what Paul was writing to them. As Christians, we are commanded to rightly divide, or accurately handle Scripture (2 Timothy 2:15), which requires intellectual effort, diligence and most importantly the Spirit guiding us in all truth (John 16:13). Without the Holy Spirit, people cannot correctly handle the Scriptures. They will either fail to understand them (2 Timothy 3:7) or distort them to their own ends. Paul and Peter, though writing to different audiences with different needs and circumstances, are both exhorting their respective churches to grow in grace, be diligent to study Scripture and be on guard against false teaching.