The Sin of Arrogance: Iblis's refusal to bow shows pride is the first sin.
Iblis's refusal to obey the divine command was based on the arrogance of his origin (fire) versus Adam's (clay), making him a permanent disbeliever. Guard against pride in your advantages. Do not let your race, wealth, education, or origin lead you to look down on others. Humility is the antidote to the first and most destructive sin.