Syedna Abu Hurairah (may Allah be pleased with him), while narrating the hadith of Isra, says: The Noble Prophet (peace and blessings be upon him) said: When I descended towards the sky of the world, I saw that below me there was dust, smoke, and noises. I said: O Jibreel! What is this? He said: These are devils, who are hovering in front of the eyes of the children of Adam, so that they may not reflect upon the kingdoms of the heavens and the earth. If they were not there, they would see wondrous things.