There was a Scottish painter named Gavin Macgregor who was very interested in making a penny where he could, so he often thinned down his paint to make it go a wee bit further.
As it happened, he got away with this for some time, but eventually the Baptist Church decided to do a big restoration job on the outside of one of their biggest buildings.
Gavin put in a bid, and, because his price was so low, he got the job.
So he set about erecting the scaffolding and setting up the planks, and buying the paint and, yes, I am sorry to say, thinning it down with water...
Well, Gavin was up on the scaffolding, painting away, the job nearly completed, when suddenly there was a horrendous clap of thunder, the sky opened, and the rain poured down washing the thinned paint from all over the church and knocking him clear off the scaffold to land on the lawn among the gravestones, surrounded by telltale puddles of the thinned and useless paint.
Gavin was no fool. He knew this was a judgment from the Almighty,
So he got down on his knees and cried:
"Oh, God, Oh God, forgive me; what should I do?"
And from the thunder, a mighty voice spoke..
(you're going to love this)
"Repaint! Repaint! And thin no more!"