David R Davis was a music minister at a small church who was invited to sing at the wedding. Out of a blue, he received a phone call from a stranger, a woman, to sing at her friend’s wedding. He declined. 

“I just said ‘No!’  “I’m not going to do it.  I didn’t get hired to sing at weddings that was just it.”  But she was very persistent, and she was nice.  So, I guess that’s why finally I opened my mouth to say No and Yes came out.”

But, he didn’t know whose wedding it was until he got there.  

“When I first got there, I went in the back and John and Carolyn were just sitting there.  He said, ‘So what you got for us?  What you’re going to sing?’”  “I had gone out of my norm to prepared myself to sing ‘Here and Now’ and ‘You and I.’ When I told them, he said ‘That’s nice.  But do you know Amazing Grace?’ Whoa, I was like ‘Yeah!’  He said ‘Amazing Grace, yeah we want that.'”

“Then senator Kennedy came and talked to me, and he had heard how I tried to get out of doing this wedding.  He said ‘I know you think you’re not supposed to be here.  But we wanted somebody here that knows about the things of God.’ And I knew by the divine providence of God is the reason that I was there. So, for the first time I was consciously glad that I did not win the fight to not do the wedding.”