1. "The things I do for love"- Courage
This is Courage's most classic quote. It's found in almost every episode as he tries desperately to save his family members from strange antagonists and finds himself wondering how he ended up there.
2. "Yes!"- Courage
Another courage classic. When things get too desperate, courage always manages to pull out one final stop and let out a fanatic "Yes!"
3. "Stupid dog! You make me look bad!"- Eustace Bagge
Family patriarch Eustace puts Courage down, always berating him with insults like "Stupid dog." More insight is given into why Eustace has such a grungy attitude when his mother visits and constantly refers to him as "stupid boy."
4. "Courage, you know I can't hear without my glasses"- Muriel Bagge
Muriel, is the portrait of a perfect dog mom. Everyone remembers her love for Courage and her incompetent attempts to provide for him, which usually led to him having to save her from some ridiculous peril. This quote exemplifies her cluelessness in the best possible way.
5. "There's no such thing as perfect. You're beautiful as you are Courage. Even with your imperfections, you can do anything."- Bathtub Barracuda
This one speaks for itself. It's the most classic quote from the show. The absurdity of a bathtub barracuda giving life advice to a cowardly dog is a fun thing to think about, but the quote obviously has a deeper meaning.