This semester I am taking Greek Exegesis of James with Dr. Plummer. Our final exam is coming up at the beginning of May. In preparation for this I am creating a short, running commentary on the text. For the reader of this blog it may seem that there is no rhyme or reason to what I choose to include but it is primarily covering aspects that I think will be pertinent for my final exam and what I want documented. Also see my post about the Greek vocabulary of James in formatted PDF and a flashcard app for mobile devices. Feel free to post any comments or questions or email me. The translation and notes are my own and do not necessarily reflect the view of Dr. Plummer.
9 Καυχάσθω δὲ ὁ ἀδελφὸς ὁ ταπεινὸς ἐν τῷ ὕψει αὐτοῦ, 10 ὁ δὲ πλούσιος ἐν τῇ ταπεινώσει αὐτοῦ, ὅτι ὡς ἄνθος χόρτου παρελεύσεται. 11 ἀνέτειλεν γὰρ ὁ ἥλιος σὺν τῷ καύσωνι καὶ ἐξήρανεν τὸν χόρτον, καὶ τὸ ἄνθος αὐτοῦ ἐξέπεσεν, καὶ ἡ εὐπρέπεια τοῦ προσώπου αὐτοῦ ἀπώλετο· οὕτως καὶ ὁ πλούσιος ἐν ταῖς πορείαις αὐτοῦ μαρανθήσεται.
9 Let the humble brother boast in his exaltation 10 and the rich (brother) in his lowly state, because like a flower of the grace it will pass away. 11 For the sun rises with its scorching heat and withers the grass, and its flower falls, and the beauty of its appearance is destroyed, so too the rich (brother) will fall away in his way of life.
Is the rich man a believer or an unbeliever? In the context of the verse I opt for the rich man as a believer. In Jas 1:9, Καυχάσθω is assumed in Jas 1:10. I would also argue that ἀδελφὸς should go along with πλούσιος too.
Also see Varner:
“While the language reminiscent of Isaiah 40:6–7 is strong, it should be noted that the verbs (παρελεύσεται in 1:10;μαρανθήσεται in 1:11) are not used of eternal punishment in other biblical passages. There is also the possibility that the fading away refers to the riches and not the eternal passing of the rich person. If we also view Jeremiah 9:23–24 as the background, it should help us to understand that the boast is not ironic but is one in which believers are encouraged to anticipate a day when riches will mean little in light of living in accordance with God’s will (4:17). Finally, the idea that a person should boast or take pride in his own condemnation seems hard to take seriously. Therefore, the entire passage is both an encouragement to poorer believers, as well as a stern warning to richer believers.” 
Runge, Steven. Discourse Grammar of the Greek New Testament : a Practical Introduction for Teaching and Exegesis. Peabody Mass.: Hendrickson Publishers Marketing, 2010., 26 ↩
William Varner, James, ed. H. Wayne House, W. Hall Harris, III and Andrew W. Pitts, Evangelical Exegetical Commentary, Jas 1:10 (Bellingham, WA: Logos Bible Software, 2012). ↩
Download the PDF here