Imam Sadiq (a.s) said: “One day when the Prophet (a.s) went to the mosque with his companions, he prostrated for so long that they suspected his health was endangered. When he finally sat up they told him that he had prostrated for such a long time that they suspected he had died. He said: “Gabriel descended to me from near God the Almighty and said: O' Muhammad! Your Lord sends His greetings and says: “I have never hurt your feelings concerning anyone of your nation who loves you. I have not done anything for a believer to please him or hurt him unless it was good for him.”“ The Prophet (a.s) added: “At that time I had no property to give away in charity, and no slave to free, so I fell prostrate in worship and thanked God and praised Him for this.”