Flying without feathers is not easy: my wings have no feathers.
Give assistance, and receive thanks lighter than a feather: injure a man, and his wrath will be like lead.
Practice yourself what you preach.
That man is worthless who knows how to receive a favor, but not how to return one.
Not by age but by capacity is wisdom acquired.
The man who masters his own soul will forever be called conqueror of conquerors.