James reminds us that often our arguments, fights, and divisions are rooted in the sin of selfish desires of the heart. He then tells us the cure for it.
The prophet Zechariah received a vision that showed him how a person is saved. He sees that salvation is by grace alone through Jesus alone, not by works.
Light helps us see where we’re going and keeps us safe. Jesus said Christians are the light of the world, but sometimes we dim that light or turn it off.