The people of king Mamun Rashid were very angry that he had made our 8th Imam, Imam Raza (as), his heir. To show Imam Raza (as) that they did not respect him, the servants of Mamun Rashid decided that when 8th Imam, Imam Raza (as) came to the court they would not open the doors, or lift up the curtains for Imam Raza (as) to pass through. That day when Imam Raza (as) came to the court, the doors and curtains were opening by themselves for Imam Raza (as) under the command of Allah. The servants became very scared and ashamed and resumed their duty of opening the doors and curtains for Imam Raza (as). Moral: No-one can do anything to you when Allah is looking after you, as Allah is the most powerful and in control of everything.
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