Every time you consider doing something you believe/know to be wrong, you have an internal conflict (of variable magnitude).
Every time you act, despite knowing it to be unacceptable, you undermine your greater sense of character and abuse your reward system.
Do the right thing and conflict will give way to resolution. Followed by positive consolidation.
Take more care not to fail once than to succeed a hundred times.
-Baltasar Gracián y Morales, 1647