Two men, one rich and one not. The rich one had two vineyards ringed with palms, crops between them, and a river running through, gardens that produced their full yield and “suffered no loss” (18:33). Everything worked. And somewhere in all that working, he started believing it worked because of him.
He told his friend, mid-conversation, “I am wealthier than you, and greater in manpower.” (18:34), then went further: “‘I do not think this will ever perish.’ ‘And I do not think the Hour is coming. And even if I am returned to my Lord, I will find something better than this in return.’” (18:35-36). His friend gave him the correction the story is built around: you should have said “Ma sha Allah, la quwwata illa billah”, what Allah wills, there is no power except with Allah (18:39). He did not. By morning the gardens were gone, and he was turning his hands over in regret, saying the words that would have saved him a day too late.