Iblis complained to Allah about Job. He said that although he was continuously glorifying Allah, he was not doing so out of his sincerity but to satisfy Allah so that his wealth should not be taken away. It was all a show, all out of greed. "If You remove his wealth then You will find that his tongue will no longer mention Your name and his praying will stop."
Allah told Iblis that Job was one of His most sincere devotees. He did not worship Him because of the favors; his worship stemmed from his heart and had nothing to do with material things. But to prove to Iblis the depth of Job's sincerity and patience, Allah allowed him to do whatever he and his helpers wished with Job's wealth.
Iblis was very happy. He gathered his helpers and set about destroying Job's cattle, servants, and farms until he was left with no possessions. Rubbing his hands in glee, Iblis appeared before Job in the guise of a wise old man and said to him: "All your wealth is lost. Some people say that it is because you gave too much charity and that you are wasting your time with your continuous prayers to Allah. Others say that Allah has brought this upon you in order to please your enemies. If Allah had the capacity to prevent harm, then He would have protected your wealth."
True to his belief, Job replied: "What Allah has taken away from me belongs to Him. I was only its trustee for a while. He gives to whom He wills and withholds from whom He wills." With these words, Job again prostrated to his Lord.