The particle oun ("then") makes definite the connection with the preceding paragraph; the picture of sin and judgment is the fresh motivation for telling the brothers now to be patient. Be patient? What an incredible command to give after the preceding portrayal of offenses! "Be outraged" is more what we would expect. But James has not lost his moral perspective in the midst of his moral passion. He has already expressed his outrage, but his concern is still for purity among the Christians, and he discerns the danger of falling into sin here. James is practicing his own counsel from 1:9-15, recognizing the danger of temptation in the midst of trials inflicted by rich oppressors. He does not tell his readers to compete with or fight against the rich for their wealth, because it would be horrible to become drawn into the materialism of the rich and so to come under the same divine judgment.
James's other alternative might be to say, "Give up in despair, for the situation is hopeless; all the power is in the hands of the rich." This, too, would be falling into sin; it would be an affirmation of the values of the rich, saying that their materialistic power is the only goal to live for.
"Both giving in to the world and attacking the world are wrong," concludes Davids (1982:182). Instead, James says, Be patient, and he spends these next five verses explaining that patience.