When should I quit something?

1 Corinthians 15:34Think carefully about what is right, and stop sinning.

Ephesians 4:28If you are a thief, quit stealing. Instead, use your hands for good hard work, and then give generously to others in need.

We should quit immediately when we are doing something wrong, when our actions are futile, or when we are hurting others. Even if an action or behavior is not inherently wrong, if it is not productive and absorbs too much of our attention or is a stumbling block to others, we should stop doing it.