I like the sentiment because it encompasses every phase of our life. It is positive, reflective and hopeful. Most of all, the saying reminds us that compassion and gratitude is within us, borne of our own experience. Why then, do we often fail to openly express our gratitude with others? Why do we need to be reminded that it is the right thing to do?
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Thank you are words that should be said, but as mother told us, actions speak louder than words. Don't worry when you don't hear the words as often as you think you should. Try harder to say thank you even when you don't believe it is necessary.
Above all, practice kindness. Being kind demonstrates your gratitude for being both a contributor and a participant in the world. Kindness is gratitude in action.