We should always note who is doing the speaking in any given biblical passage, as that bit of contextual information will help us rightly interpret it. Although everything in the Bible is inspired to be in the Bible, not everything in the Bible is the inspired Word of God. What do I mean?
In many passages of Scripture, the uninspired words of people are recorded. Therefore, we shouldn’t think that everything spoken by people in the Bible is inspired by God.
For example, some make the error of quoting the words of Job and his friends as if they were the inspired words of God. There are two reasons why this is a mistake. First, Job and his friends argued for thirty-four chapters. They disagreed. Obviously not everything they said could be God’s inspired Word because God doesn’t contradict Himself.
Second, at the close of the book of Job, God Himself speaks, and He rebukes both Job and his friends for saying things that were not correct (see Job 38-42).
We must take the same precautions when reading the New Testament. In several cases, Paul plainly stated that certain portions of his writings were only his own opinions (see 1 Cor. 7:12, 25-26, 40).