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