1 Πόθεν πόλεμοι καὶ πόθεν μάχαι ἐν ὑμῖν; οὐκ ἐντεῦθεν, ἐκ τῶν ἡδονῶν ὑμῶν τῶν στρατευομένων ἐν τοῖς μέλεσιν ὑμῶν; 2 ἐπιθυμεῖτε, καὶ οὐκ ἔχετε· φονεύετε καὶ ζηλοῦτε, καὶ οὐ δύνασθε ἐπιτυχεῖν· μάχεσθε καὶ πολεμεῖτε. οὐκ ἔχετε διὰ τὸ μὴ αἰτεῖσθαι ὑμᾶς· 3 αἰτεῖτε καὶ οὐ λαμβάνετε, διότι κακῶς αἰτεῖσθε, ἵνα ἐν ταῖς ἡδοναῖς ὑμῶν δαπανήσητε.
I don't think this means simply 'desires', ἐπιθυμέω would be more appropriate for that. And in this context, there's no reference to the kind of hedonistic pleasures I sometimes associated with hedonism.
The word is used in 3 other places in the GNT. In Luke 8, it refers to the cares and pleasures of this world:
τὸ δὲ εἰς τὰς ἀκάνθας πεσόν, οὗτοί εἰσιν οἱ ἀκούσαντες, καὶ ὑπὸ μεριμνῶν καὶ πλούτου καὶ ἡδονῶν τοῦ βίου πορευόμενοι συμπνίγονται καὶ οὐ τελεσφοροῦσιν.
In Titus 3:3 it speaks of slaves to various passions and pleasures:
ἦμεν γάρ ποτε καὶ ἡμεῖς ἀνόητοι, ἀπειθεῖς, πλανώμενοι, δουλεύοντες ἐπιθυμίαις καὶ ἡδοναῖς ποικίλαις, ἐν κακίᾳ καὶ φθόνῳ διάγοντες, στυγητοί, μισοῦντες ἀλλήλους.
In 2 Peter 2:13 it refers to those who consider it pleasure to revel in the daytime:
ἀδικούμενοι μισθὸν ἀδικίας· ἡδονὴν ἡγούμενοι τὴν ἐν ἡμέρᾳ τρυφήν, σπίλοι καὶ μῶμοι ἐντρυφῶντες ἐν ταῖς ἀπάταις αὐτῶν συνευωχούμενοι ὑμῖν
Does James refer to these same kinds of pleasures in James 4? If so, I can't quite make sense of it ...
LSJ speaks of 'malicious pleasure':
of malicious pleasure, ἡ ἐπὶ τοῖς τῶν φίλων κακοῖς, ἐπὶ ταῖς λοιδορίαις ἡ., Id.Phlb.50a, D.18.138; ἡδονῇ ἡσσᾶσθαι, ἡδοναῖς χαρίζεσθαι
The first reference is tempting, it speaks of pleasure in the misfortune of friends, but I don't see anything in James 4 to suggest this meaning:
ἡδονὴν δὲ ἐπὶ τοῖς τῶν φίλων κακοῖς, οὐ φθόνον ἔφαμεν εἶναι τὸν τοῦτ᾽ ἀπεργαζόμενον;
The second reference refers to a "joy in abusive language". Goodwin's notes on the passage say this:
. τῆς...ἡδονῆς καὶ χάριτος: abusive language (λοιδορία) not only pleased the populace, but also gratified their whims and low tastes. A good example of both ἡδονή and χάρις is the scene in the Assembly when the second embassy reported in July 346 B.C., described in XIX. 44—46. Demosthenes was insulted and jeered at by Aeschines and Philocrates, to the delight of the people: notice the single sarcastic remark of Demosthenes (46), καὶ ὑμεῖς ἐγελᾶτε. Hist. §§ 34, 35.
Could something like that be intended in James 4? Even that is hard to fit to the context ...