“When I do good, I feel good.
When i do bad, I feel bad.”
This statement by Lincoln is trying to say that your mood will and always will be determine on the actions you do. If you do everything the right way and are helpful, your life will be a lot more peaceful and smoother compared to the average lives. If you choose to the wrong things, karma will catch up to you and effect your life in a negative way and set you back from any goals or accomplishments from being done.