Simply put, Paul's justification is the justification of the ungodly--that is, becoming righteous, through faith. While James' justification is the justification of the righteous.--showing one to already be righteous, through what they do.
Justifying the righteous?
James teaches the principle of obedience, concerning faith.
Faith for salvation.
That's the context.
14 What
does it profit, my brethren, if someone says he has faith but does not have works?
Can faith save him? 15 If a brother or sister is naked and destitute of daily food, 16 and one of you says to them, “Depart in peace, be warmed and filled,” but you do not give them the things which are needed for the body, what
does it profit? 17 Thus also faith by itself, if it does not have works, is dead.
18 But someone will say, “You have faith, and I have works.” Show me your faith without your works, and I will show you my faith by my works. 19 You believe that there is one God. You do well.
Even the demons believe—and tremble! 20 But do you want to know, O foolish man, that faith without works is dead?21 Was not Abraham our father justified by works when he offered Isaac his son on the altar? 22 Do you see that faith was working together with his works, and
by works faith was made perfect? 23 And the Scripture was fulfilled which says, “Abraham believed God, and it was accounted to him for righteousness.” And he was called the friend of God. 24 You see then that a man is justified by works, and not by faith only.
25 Likewise, was not Rahab the harlot also justified by works when she received the messengers and sent
them out another way?
26 For as the body without the spirit is dead, so faith without works is dead also.
James 2:14-26
- Faith for salvation is incomplete, and dead, without the corresponding act of obedience.
...and saying, “The time is fulfilled, and the kingdom of God is at hand. Repent,
and believe in the gospel.”
Mark 1:15
...to open their eyes,
in order to turn them from darkness to light, and from the power of Satan to God,
that they may receive forgiveness of sins and an inheritance among those who are sanctified by faith in Me.’
- Faith for healing, is incomplete and dead without the corresponding act of obedience.
20 And suddenly, a woman who had a flow of blood for twelve years
came from behind and touched the hem of His garment. 21 For she said to herself,
“If only I may touch His garment, I shall be made well.” 22 But Jesus turned around, and when He saw her He said, “Be of good cheer, daughter; your faith has made you well.” And the woman was made well from that hour.
Matthew 9:20
- Faith for deliverance, is incomplete and dead without the corresponding act of obedience.
But Jesus said to her, “Let the children be filled first, for it is not good to take the children’s bread and throw
it to the little dogs.”
And she answered and said to Him, “Yes, Lord, yet even the little dogs under the table eat from the children’s crumbs.”
Then He said to her, “
For this saying go your way; the demon has gone out of your daughter.”
Mark 7:27-29
The principle of faith requires the action of obedience for it to be complete, and able to produce a divine result.
Just as a body without the spirit is dead and unable to function, so faith without the corresponding act of obedience is dead, being incomplete and unable to produce a divine result.
JLB