Who said "Kindness costs nothing but yields everything."?

This quote is attributed to Leonidas I.

Kindness costs nothing but yields everything. - Leonidas I

"Kindness costs nothing but yields everything."

Leonidas I Kindness

King Warrior Ancient Greece 540–480

"This is Sparta!"

"Spartans! Tonight we dine in hell!"

"A man's true measure is taken not in a moment of comfort and convenience, but in a moment of challenge and adversity."

"Freedom isn't free, it requires sacrifice and courage."

"A good man treats his wife with respect."

"Kindness always comes back around."

"The power of a smile can change everything."

"Kindness is weakness to some. Not to me."