We interact with a lot of people in our life. We share moments, constantly. Sometimes we may share a long length of time with a person and remain unchanged. Other times, we can have a brief exchange, an intimate encounter, or a timely interaction and it stays with us forever.
It is hard to say why, or how, or even what. But you see it, you know it in your heart and feel it coursing through your veins. You have been changed, blessed, impacted. You can never repay their kindness and generosity, just as the earth can never repay the sun for its light and warmth. You don't have to repay it; just share it, amplify it and give it to others.