I really like this quote. I think this is a philosophy that everyone should embrace and live up to. The 'poor lil ole me' frame of mind does not sit well with me. We all need a 'can do' attitude, whether it amounts to a mountain or a mole hill in our eyes.
When the idea of being just one person and what can I do comes up, I think of two people. First, Adam's fall from grace destined sin to be in the lives of mankind forever. That was a pretty big impact he made for our lives. Secondly, God sent one man to save us from sin.. Jesus. The One taught us, died for us, redeemed us and loves us.
We can each do something and that is why we are each given different fruits of the spirit. We aren't all the same and that is why the church body works together for the benefit of the whole.
We can all claim 'interference', like in a football game, to blocking our actions but that shouldn't stop us from trying. Make a play, don't hold back.
You were made by design to fulfill His plan, go and do it without hesitation.