When Iblis saw this, he felt frustrated, so he again addressed Allah: "I have stripped Job of all his possessions, but he still remains grateful to You. However, he is only hiding his disappointment, for he places great store by his many children. The real test of a parent is through his children. You will then see how Job will reject You."
Allah granted Iblis authority, but warned him that it would not reduce Job's faith in his Lord nor his patience.
Iblis again gathered his helpers and set about his evil deeds. He shook the foundation of the house in which Job's children were living and sent the building crashing, killing all of them. Then he went to Job disguised as a man who had come to sympathize with him. In a comforting tone he said to Job: 'The circumstances under which your children died were sad. Surely, your Lord is not rewarding you properly for all your prayers." Having said this, Iblis waited anxiously, hoping Job was now ready to reject Allah.
But again Job disappointed him by replying: "Allah sometimes gives and sometimes takes. He is sometimes pleased and sometimes displeased with our deeds. Whether a thing is beneficial or harmful to me, I will remain firm in my belief and remain thankful to my Creator." Then Job prostrated to his Lord. At this Iblis was extremely vexed.