Themes
When I do good, I feel good; when I do bad, I feel bad. That's my religion.
— Abraham Lincoln

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker describes a personal religion reduced to a simple moral rule: doing right brings a good feeling and doing wrong brings a bad one. Conscience is the guide, with no need for elaborate doctrine. The plainness is the point, making goodness a matter of everyday conduct and its inner consequences.
Context reviewed