All the mistakes I ever made were when I wanted to say 'No' and said 'Yes'. -- Moss Hart
Some suggestions for you :
Don't gain the world and lose your soul; wisdom is better than silver or gold.
It's hard to lead a cavalry charge if you think you look funny on a horse.
Blessed are the young, for they shall inherit the national debt.
When a good man is hurt, all who would be called good must suffer with him.
When you advise any person you should be guided by the fear of God.
We often miss opportunity because it's dressed in overalls and looks like work.