I shall pass through this world but once. Any good therefore that I can do, or any kindness that I can show to any human being, let me do it now. Let me not defer not neglect it, for I shall not pass this way again.
Kindness is an inner desire that makes us want to do good things even if we do not get anything in return. It is the joy of our life to do them. When we do good things from this inner desire, there is kindness in everything we think, say, want and do.