The ideas of trials, joy, persistent faith, wisdom, and doubt in 1.2-7 are all further discussed as James continues.
James' three exhortations in 1.19 are likewise foundational: be quick to hear; slow to speak; and slow to anger. They are all immediately returned to in 1.20-21, 1.22-25, and 1.26-27. However, some believe that 1.19 helps to shape the train of thought for the next few chapters: correctly hearing the word [ch 2], the difficulty of controlling the tongue [ch 3], and the damaging effect of angry speech [ch 4]. I was helped here by William Baker.
The thing about the flow of thought that is downright convicting is that once James concludes his discussion on faith and works in ch 2, he then moves into a discussion on the tongue and how it "is set on fire by hell itself" [3.6]. Those ideas aren't far from one another in his mind. Essentially, my faith should evidence the worth of the object of my faith. One of the ultimate ways it does this is by what comes out of my mouth. That stings a bit.
Lastly, I love Js 1.5: "If any of you lacks wisdom, let him ask of God." Meaning, you all lack wisdom. I also love Js 3.13: "Who among you is wise and understanding?" Meaning, there is none who needs stunted growth in wisdom. So, James gives an excellent comparison between the earthly wisdom and heavenly wisdom [3.14-18].
Earthly wisdom is first cousins with bitter jealousy and selfish ambition; it is arrogant; it cooperates with demons and is exercised in the context of disorder.Heavenly wisdom is first pure, then peaceable, gentle, reasonable, full of mercy, full of good fruits, unwavering, and without hypocrisy.