Answer: Faith by itself, when not accompanied by action, is a dead faith, (verse 17).
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The illustration of false faith in these verses is parallel to the illustration of false love found in 1 John 3:17, which calls for love in action. These verses call for faith in action. It is false to claim that there are "faith" Christians and "deeds" Christians--a claim that faith and deeds can exist independently of each other. James here denies the possibility of you showing him, or anyone else, your faith without deeds (verse 18).
If you set apart these verses from their context, they seem to contradict the Biblical teaching that people are saved by faith and not by good deeds. (Romans 3:28: "For we maintain that a man is justified by faith apart from observing the law." Galatians 2:15-16: "We who are Jews by birth and not ‘Gentile sinners' know that a man is not justified by observing the law, but by faith in Jesus Christ. So we, too, have put our faith in Christ Jesus that we may be justified by faith in Christ and not by observing the law, because by observing the law no one will be justified.")
But James means only that righteous action is EVIDENCE of genuine faith--not that it saves. The verse that James cites in verse 23 to substantiate his point is Genesis 15:6: "Abram believed the Lord, and He credited it ["it" being faith, not works] to him as righteousness." Furthermore, Abraham's act of faith recorded in Genesis 15:6 occurred BEFORE he offered up Isaac, which was only a proof of the genuineness of his faith. As Paul wrote, "The only thing that counts is faith expressing itself through love," (Galatians 5:6). Faith that saves produces deeds--not deeds as a means of salvation, but works as proof of faith.
The Greek literal translation says "if your ‘faith' keeps on not having works"--in other words, faith that is lip service only, and which never produces any works--is already dead, and the one professing such a "faith" is still dead in sin.
In verse 20, James calls such people (those who profess their "faith" but do not prove it by their actions) "foolish." In the original Greek, this means "empty," "empty-headed," "empty-handed," "empty-hearted." It has been compared to the "Raca" of Matthew 5:22, inferring that these teachings refer more to the attitude of the heart than the letter of the Word. ("Raca" was a word of utter contempt, signifying being intellectually empty rather than morally empty--empty-headed! Quoting from Vine's Expository Dictionary of Old and New Testament Words, "As condemned by Christ, Matthew 5:22, it [Raca] was worse than being angry, inasmuch as an outrageous utterance is worse than a feeling unexpressed or somewhat controlled in expression; it does not indicate such a loss of self-control as the word rendered "fool," [meaning] "a godless, moral reprobate." Here in James 2:20, James is not cursing another, but he is simply stating the fact that a person is foolish (empty, empty-headed, empty-handed, empty-hearted) who professes faith, but does not prove that faith by his actions.)
One cannot have faith without ACTIONS any more than one can have love without ACTIONS. Having a "faith" without works is refusing to acknowledge that we are God's workmanship, His new creation in Christ to do good works--works which GOD prepared in advance for us to DO! By having "faith" without works, we become AGAIN objects of God's wrath--even more so than before we heard and obeyed the Truth by faith. (Read Hebrews 10:26-31.)
Ephesians 2:1-10 sums up all of this very well:
"As for you, you were dead in your transgressions and sins, in which you used to live when you followed the ways of this world and of the ruler of the kingdom of the air, the spirit who is now at work in those who are disobedient. All of us also lived among them at one time, gratifying the cravings of our sinful nature and following its desires and thoughts. Like the rest, we were by nature objects of wrath. But because of His great love for us, God, Who is rich in mercy, made us alive with Christ even when we were dead in transgressions--it is by grace you have been saved. And God raised us up with Christ and seated us with Him in the heavenly realms in Christ Jesus, in order that in the coming ages He might show the incomparable riches of His grace, expressed in His kindness to us in Christ Jesus. For it is by grace you have been saved, through faith--and this not from yourselves, it is the gift of God--not by works, so that no one can boast. For we are God's workmanship, created in Christ Jesus to do good works, which God prepared in advance for us to do."
How can we, children of God by faith in Christ Jesus, fail to do less than our Savior did? We must obey His command and follow His example:
Matthew 20:26-28: [Jesus said,] "Not so with you. Instead, whoever wants to become great among you must be your servant, and whoever wants to be first must be your slave--just as the Son of Man did not come to be served, but to serve, and to give His life as a ransom for many." (See also Mark 10:43-45.)
Mark 9:35: "Sitting down, Jesus called the Twelve and said, ‘If anyone wants to be first, he must be the very last, and the servant of all.'"