The book of James is a short book in the New Testament and it deals a lot with wisdom teachings of Jesus.
I think what we have in James is an elaboration of some of the things that Jesus taught in a way that helps us understand how God wants us to live in this age, how He wants us to relate to one another, how He wants us to seek wisdom. And that's one of the first parts of James. James tells us if we lack wisdom, we should ask God who gives, but we should ask in faith.
And so James shows us how James the author, how he elaborates the words of Jesus, the teachings of Jesus, and applies those to us where we are today in some very practical ways, for what it looks like to live out the Christian life in this world.