During a Jumah Khutbah in a small town, an Imam talked about the significance of saying "Insha Allah" (which means if Allah wills) when planning to do something in the future. After a few days, a man who had also attended the Khutbah was going to buy a cow from the market. On the way, he met a friend who asked him where he was going. He told him about buying the cow but did not say Insha Allah in the end. His friend reminded him about the Khutbah and told him to say Insha Allah. However, this individual said that he had the money he needs and the energy to go to the market, thus, there is no point of saying Insha Allah as he will certainly buy the cow. He thought that saying Insha Allah will not make any difference.
When he reached the market, he found a cow that met his expectations. He burgained with the seller and came to a reasonable price. Finally, he decided to pay for the cow but was dumbfounded when he discovered that his money was missing. A thief had stolen the money while he was walking through the busy market. The cow seller asked him whether he was going to buy the cow or not. "Insha Allah, I will buy it next week," he said. When he reached home, his wife inquired about the cow. He told her about how he forgot to say Insha Allah, and also added, "Insha Allah, I wanted to buy the cow. But Insha Allah, my money was stolen. Insha Allah, I will buy it next week." His wife clarified to him that we should say Insha Allah for things that are yet to happen, not for those things that had already happened. He never forgot his "Insha Allah" again.
This incident was narrated by Shaikh Wahidullah from Toronto, Canada.