James 2:19 reads, "You believe that there is one God. You do well. Even the demons believe - and tremble!" Some Christians use this verse to argue that the faith that saves must be proved by works or it is not genuine. The argument goes like this: "A person who says that he believes in Jesus Christ as Savior, but does not do good works is not really saved. He is like the demons who believe in God but are not saved because they have not submitted to God or obeyed Him." This is a careless misuse of the verse.
It is surprising that James 2:19 is used so often when a few simple observations would disarm the argument that it proves the necessity of works for saving faith.
First, this verse is not about eternal salvation, because demons cannot be saved. Their fate and condemnation is sealed (Matt. 8:29; 25:41; Jude 6). That is why they tremble when they think of God.
Second, the object of the demons' faith is the fact that there is one God, that is, monotheism. No one is saved by belief in monotheism anyway, so this verse is not used soteriologically. Many of the world's non-Christian religions are monotheistic.
Third, it does not say that the demons believe in Jesus Christ as their Savior. Jesus Christ did not die and rise from death to save demons but humans. While Christ's work saves humans, it destroys the devil (Heb. 2:14).
Fourth, a quick survey of commentaries shows the difficulty of properly interpreting this verse in the context of James 2:16-20. At question is when James' words end and the objector's words begin and end. If, as some argue, verse 19 is spoken by an objector to James, should it be used to prove a crucial theological point? Also, if it is from such a difficult passage to interpret, should it be used as a primary text to prove or disprove anyone's salvation? Much clearer passages dismiss works as necessary for obtaining eternal salvation (eg., Rom. 4:4-5; Eph. 2:8-10; Titus 3:4-5).
The book of James is written to Jewish Christians (see GraceNotes No. 2) to encourage them to become mature by responding to trials in faith (1:2-4). The section of 2:14-26 is also addressing the Christian readers as "my brethren." James is arguing that a Christian who only declares his faith but does no good is of no help to those in need (2:14-16) and his or her faith is therefore "dead" or useless (2:17, 20). A workless faith is also worthless in saving a Christian from a merciless judgment at the Judgment Seat of Christ, a judgment for Christians where they will be held accountable for how they lived (Rom. 14:10-12; 2 Cor. 5:10). This judgment for Christians is mentioned at both ends of this section, in 2:13 and 3:1, showing it governs James' thinking about the relationship of works to faith.
James 2:19 does show that faith is faith. There are not different kinds of faith, but different objects of faith. It is not the kind of faith or the reality of faith that is being questioned, it is the object of faith and the usefulness of one's faith. The reality of the demons' faith is not questioned, but they only believe that there is one God. They truly believe that, and that is why they tremble in fear of their judgment.
James 2:19 should not be used to argue that works are needed to prove saving faith. This verse shows that demons have a real faith. They believe in one God and know that God has sealed their fate in judgment, therefore they tremble. But they do not and cannot believe in Jesus Christ as their Savior. While good works are God's purpose for us, are useful to others, and give us a good evaluation at the Judgment Seat of Christ, they cannot prove or disprove the reality of saving faith. Eternal salvation is by grace alone through faith alone - apart from any works at any time.