I don't believe it's a Paul or James issue really. They both are saying the same thing - allow me to explain.
First, all James is saying, is that if someone claims to be saved, yet doesn't have works to prove of their salvation, then they aren't saved. Their faith is useless, because it isn't attributed to them as righteousness until it impacts the way they live their life. Once their lives change to reflect that faith, then they are saved, but not by their works, by faith. The perfection of the faith, is the coupling of faith and works. Works alone, nor faith alone can save someone.
As regarding Paul, Paul does seem as if he's saying exactly the opposite, but mainly that's because of Paul's strange writing style.
Peter addresses it here:
2 Peter 3:14-18
14So then, dear friends, since you are looking forward to this,
make every effort to be found spotless, blameless and at peace with him.
15Bear in mind that our Lord’s patience means salvation, j
ust as our dear brother Paul also wrote you with the wisdom that God gave him. 16He writes the same way in all his letters, speaking in them of these matters.
His letters contain some things that are hard to understand, which ignorant and unstable people distort, as they do the other Scriptures, to their own destruction.
17Therefore, dear friends, since you have been forewarned,
be on your guard so that you may not be carried away by the error of the lawless and fall from your secure position.
18But grow in the grace and knowledge of our Lord and Savior Jesus Christ. To him be glory both now and forever! Amen.
Peter was addressing the issue that was going on at the time. Paul was being accused of doing away with the law of God, but Peter himself, as well as a few other people all backed Paul up, saying that Paul never taught against the law, and that he actually taught and kept the law, but that his writings are crazy confusing, and that people often mixed up what he was saying. He was almost put to death several times for this, which is why Peter addressed it, because it was confusing people. It was causing people to (as verse 17 says) get carried away by the error of lawlessness, because it seemed as if he was saying the opposite of what he meant.
I mean I can link verse after verse of Paul keeping the biblical feasts, and writing to gentiles on how they are to keep the feast of unleavened bread, him teaching gentiles on the sabbath, etc. There are several contradictions throughout scriptures like this, but only from the perspective that the law is done away with. Jesus Himself said that it wouldn't be done away with until the heavens and the earth passed away, but yet there's verses in the psalms and proverbs and prophets saying that His heavens are eternal. Jesus wasn't saying that the law would pass, He was basically saying that "when pigs fly".
By believing in Jesus, according to Romans 11, you become Israel, and you
get to partake of the instruction of God. You don't have to. It's the fruit of your salvation, not the root of it. The law of God, isn't a burden. The burden, is when men make a bunch of their own laws to put on top of it. I've been practicing Torah for almost a year now, and I've learned more, come closer to God and have grown in so many ways. It's been an absolute blessing, but He doesn't expect you to be perfect in it, it's something you learn and grow in.