He that does a base thing in zeal for his friend burns the golden thread that ties their hearts together.

Loyalty that crosses into wrongdoing damages the friendship it was meant to serve. The moment you lie, cheat or harm someone on a friend’s behalf, you have shown them what you are capable of, and they cannot un-know it. Even if they wanted the favour, something between you thins afterwards, because trust rests on the limits a person keeps rather than the ones they will break for you.

When a friend asks for something you would not do for yourself, say so plainly and offer what you can do instead. Being the person who holds a line is a better gift than being the person who will do anything.