There is no evidence of true faith doing vs. 16, those are just empty words. We have excellent examples of true faith in Scripture, and in all of them their faith was evidenced by works. It is not different in our time. Even demons demonstrate their "faith" (not for salvation), shuddering.
What good is it, my brothers,
Τί τὸ ὄφελος, ἀδελφοί μου,
if someone says he has faith
ἐὰν πίστιν λέγῃ τις ἔχειν
o but does not have works?
ἔργα δὲ μὴ ἔχῃ ;
Can that faith save him?
μὴ δύναται ἡ πίστις σῶσαι αὐτόν;
p If a brother or sister is poorly clothed and lacking in daily food,
ἐὰν ἀδελφὸς ἢ ἀδελφὴ γυμνοὶ ὑπάρχωσιν καὶ λειπόμενοι ὦσιν τῆς ἐφημέρου τροφῆς
q and one of you says to them,
εἴπῃ δέ τις αὐτοῖς ἐξ ὑμῶν•
“Go in peace,
ὑπάγετε ἐν εἰρήνῃ,
καὶ χορτάζεσθε ,
without giving them the things needed for the body,
μὴ δῶτε δὲ αὐτοῖς τὰ ἐπιτήδεια τοῦ σώματος,
what good 1 is that?
τί τὸ ὄφελος;
So also faith by itself, ... is dead,
οὕτως καὶ ἡ πίστις, ... νεκρά ἐστιν καθʼ ἑαυτήν,
[⇡] if it does not have works.
[⇡] ἐὰν μὴ ἔχῃ ἔργα.
But someone will say,
Ἀλλʼ ἐρεῖ τις•
“You have faith
σὺ πίστιν ἔχεις ,
and I have works. ”
κἀγὼ ἔργα ἔχω •
Show me your faith r apart from your works,
δεῖξόν μοι τὴν πίστιν σου χωρὶς τῶν ἔργων,
and I will show you my faith s by my works.
κἀγώ σοι δείξω ἐκ τῶν ἔργων μου τὴν πίστιν.
t You believe
that God is one;
ὅτι εἷς ἐστιν ὁ θεός,
you do well.
καλῶς ποιεῖς •
Even u the demons believe—
καὶ τὰ δαιμόνια πιστεύουσιν
καὶ φρίσσουσιν .
Do you want to be shown, you foolish person, that faith apart from works is useless?
Θέλεις δὲ γνῶναι , ὦ ἄνθρωπε κενέ, ὅτι ἡ πίστις χωρὶς τῶν ἔργων ἀργή ἐστιν ;
v Was not Abraham our father justified by works
Ἀβραὰμ ὁ πατὴρ ἡμῶν οὐκ ἐξ ἔργων ἐδικαιώθη
when he offered up his son Isaac on the altar?
ἀνενέγκας Ἰσαὰκ τὸν υἱὸν αὐτοῦ ἐπὶ τὸ θυσιαστήριον;
that w faith was active along with his works,
ὅτι ἡ πίστις συνήργει τοῖς ἔργοις αὐτοῦ
and faith was completed x by his works;
καὶ ἐκ τῶν ἔργων ἡ πίστις ἐτελειώθη ,
and the Scripture was fulfilled that says,
καὶ ἐπληρώθη ἡ γραφὴ ἡ λέγουσα •
y “Abraham believed God,
ἐπίστευσεν δὲ Ἀβραὰμ τῷ θεῷ,
and it was counted to him as righteousness”—
καὶ ἐλογίσθη αὐτῷ εἰς δικαιοσύνην
and he was called a z friend of God.
καὶ φίλος θεοῦ ἐκλήθη .
that a person is justified by works
ὅτι ἐξ ἔργων δικαιοῦται ἄνθρωπος
and not by faith alone.
καὶ οὐκ ἐκ πίστεως μόνον.
And in the same way was not also a Rahab the prostitute justified by works
ὁμοίως δὲ καὶ Ῥαὰβ ἡ πόρνη οὐκ ἐξ ἔργων ἐδικαιώθη
b when she received the messengers
ὑποδεξαμένη τοὺς ἀγγέλους
and sent them out by another way?
καὶ ἑτέρᾳ ὁδῷ ἐκβαλοῦσα ;
For as the body apart from the spirit is dead,
ὥσπερ γὰρ τὸ σῶμα χωρὶς πνεύματος νεκρόν ἐστιν ,
so also faith apart from works is dead.[”]
οὕτως καὶ ἡ πίστις χωρὶς ἔργων νεκρά ἐστιν .
This takes me back to the vs. 1-13. Don't pretend that this is about using "nice words", you need to really love your brothers.
Rhetorical question #1 - There is no good if (when) someone says he has faith but does not have works.
Rhetorical question #2 - That kind of faith cannot save him.
Rhetorical question #3 - There is no good in that.
Rhetorical question #4 - Let me show you through some examples that faith apart from works is useless.
Rhetorical question #5 - Abraham was justified by works when he offered up his son Isaac on the altar.
Rhetorical question #6 - In the same way Rahab was justified by works when she received the messengers and sent them out by another way.
Given the context, the importance is not in the timing of the event, but in how that happened.
You have faith, and I, besides faith, have works, therefore you are not able to show your faith because you don't have works, but on the contrary, I have my works as an evidence of my faith.
Therefore, you shouldn't be satisfied by your workless belief that God is one, because even the demons believe that, but with different result than yours, they shudder.
Sarcasm? Of course you should believe that, because even demons do it, but they also shudder as a result of this belief.
Stressing the point - Even Rahab, who was a Gentile and a prostitute showed her faith by her works.
If this is James talking, who is the foolish person? I think that this could be a continuation of the correction (response) of the second "someone".
6 For in Christ Jesus e neither circumcision nor uncircumcision counts for anything , but f only faith working through love .
1 John 3:17-18
17 But f if anyone has the world’s goods and sees his brother in need, yet g closes his heart against him, h how does God’s love abide in him? 18 Little children, let us not i love in word or talk but in deed and j in truth .
2 Corinthians 13:5
5 Examine yourselves , to see whether you are in the faith. v Test yourselves . Or do you not realize this about yourselves, that w Jesus Christ is in you?—unless indeed you fail to meet the test !