The truly powerful are so because they have few vulnerabilities. Vulnerability comes from having to worry about what you have. One can't exploit the man who has nothing. If you freely give of your treasure, there is nothing for which someone must contend with you to get. Anytime you have power, if you share it with others, it reduces the hold your adversary might have against you. If you expose your weaknesses and embrace them, there can be no surprise attacks against your character.
There is a story about a man who was sitting under an ancient tree. The spirit of the tree said to him, "I got so old because I can not be exploited. My trunk is knotted and not fit to make into boats. My limbs are gnarled and unsuitable for timbers."
Real leaders don't fear empowering their followers. By empowering these people, real leaders gain allies. Doing so gains these leaders even more power. Real leaders share their knowledge with others. They aren't afraid to enlighten those who desire wisdom because good pupils will always appreciate their masters, especially if they have fond memories of their experiences together.
In giving of yourself, you gain more in return. The tighter you hold power, the more likely you will crush it like an ember and exhaust it. Give power to those in need and it will come back to you much more so than what you gave away.