What does this quote mean it takes a great deal of courage to stand up to your enemies but even more to stand up to your friends?

It means that you have to be brave to stand up against your enemies if you disagree with what they are doing; but it takes a lot more bravery to stand up against your friends if they are doing something you disagree with. This is because you are less likely to value an enemies opinion; getting into a fight or argument with an enemy means you have nothing to loose because you didn't get on with them in a first place and you aren't risking loosing a friendship. If you stand up against a friend there is a chance you could fall out and loose a friend so you must be a lot braver to stand up against them. Hope this helped.