What is the difference between compassion and pity?

Pity is when you feel sorry for someone, but it doesn't come from your heart. Pity doesn't help anyone but compassion does. You will notice in the Gospels that "Jesus was moved with compassion for the multitudes" is mentioned several times. He saw their spiritual state and felt compassion for them, to help with their needs. You can feel pity for someone all day long, but when you feel compassion and empathy for someone you will be moved to action to help them in some way, hopefully.