The author identifies himself as James in the first verse but as there are four James in the New Testament it is concluded by process of elimination that this James is the half brother of Jesus. James the apostle was martyred too early (around 44 AD) to have written it. The other two James did not have the stature that the writer of this book had. This is the most assuredly the James who led the early church of Jerusalem by Acts 15.
Date: around 49 AD
This or the letter of Galatians was likely the first book written of the New Testament. There are several reasons to believe an early writing, specifically before 50 AD when the Jerusalem Council of Acts 15 was held.
The fact that this is a more Jewish letter implies that the church was more Jewish at its writing; so does the fact that its meeting place is the synagogue (which obviously wouldn’t have allowed Gentiles in). The lack of reference to the controversy of circumcision among Gentile believers implies that this was written before the problem arose in the church.
Recipients: Jewish Christians
The letter is addressed to the “twelve tribes” and thus is intended for the Jews. However, it is also obvious that this is written to Christians. Some try to spiritualize most New Testament references to Jews as being to Christians but given the context of the book, it appears most likely that James is writing specifically to Jewish Christians as there would be few Gentile Christians at the time but also the Jewish Christians would be dealing with different issues.
Suffering – James opens his letter admonishing the recipients to hold fast during trials and temptations. He closes it by preaching patience in suffering.
Wisdom – James speaks a lot on wisdom and draws some parallels with the book of Proverbs
Faith and Deeds – The biggest theological idea in James concerns the balance needed between having faith and expressing that faith through deeds.
Martin Luther did not like the book of James because of its emphasis on deeds. While he misinterpreted James’ teaching concerning deeds, Luther felt that it was too similar to the Catholic tradition that he had rejected. Because of this, Luther placed the book of James last, behind the book of Revelation, in his German translation of the Bible.