"The only truth I know," I would tell them, "is that if you're going to be great, then you're great now. And you know it. You know it right now. Only you can't believe it. You just need some prodding and you need some proof."
That's from Barry Manilow, speaking about his work among High School Music students back in the 1970's. From his book Sweet Life: Adventures on the Way to Paradise, p. 230
"In hope against hope he believed, so that he might become a father of many nations according to that which had been spoken, “SO SHALL YOUR DESCENDANTS BE.” Without becoming weak in faith he contemplated his own body, now as good as dead since he was about a hundred years old, and the deadness of Sarah’s womb; yet, with respect to the promise of God, he did not waver in unbelief but grew strong in faith, giving glory to God, and being fully assured that what God had promised, He was able also to perform. Therefore IT WAS ALSO CREDITED TO HIM AS RIGHTEOUSNESS." -Romans 4:18-22
