When 2 Tm 3:16 says, All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God may be complete, thoroughly equipped for every good work., does that include the Epistle of James?
Well, look at history.
From the day Paul wrote his letters they were used as the main guide in doctrine and considered sacred scripture.
It took close to two hundred years before James’ one little letter was considered sacred scripture, and even then it was put in the back of the book with the other scriptures the early Christians were not sure about.
But that one little leter has caused more problems as so many people now use it to cancel all the grace and libety letters from Paul.
Again, James’ letter was to THE TWELVE TRIBES OF ISRAEL, not the Gentile believers.
Act 21:20 And when they heard [it], they glorified the Lord, and said unto him, Thou seest, brother, how many thousands of Jews there are which believe; and they are all zealous of the law:
Act 21:21 And they are informed of thee, that thou teachest all the Jews which are among the Gentiles to forsake Moses, saying that they ought not to circumcise [their] children, neither to walk after the customs.
Act 21:22 What is it therefore? the multitude must needs come together: for they will hear that thou art come.
Act 21:23 Do therefore this that we say to thee: We have four men which have a vow on them;
Act 21:24 Them take, and purify thyself with them, and be at charges with them, that they may shave [their] heads: and all may know that those things, whereof they were informed concerning thee, are nothing; but [that] thou thyself also walkest orderly, and keepest the law.
Act 21:25 As touching the Gentiles which believe, we have written [and] concluded that they observe no such thing, save only that they keep themselves from [things] offered to idols, and from blood, and from strangled, and from fornication.