Sayyiduna Abu Wa’il Shaqiq bin Salamah (may Allah have mercy on him) says: We received a letter from Sayyiduna Umar bin Khattab (may Allah be pleased with him) in Khaniqin regarding the sighting of the Ramadan moon. Some had fasted and some had broken their fast, but no one objected to the other. The letter stated:“When you see the moon during the day, do not break your fast until two witnesses testify that they saw the moon the previous day. And when, during a siege, it is said to the people of a fortress to come down according to Allah’s command, then let them come down according to your decision, because you do not know what Allah’s command is regarding them. And if you say «لا بأس» or «لا تدخل» or «مطرس» , then this is a guarantee of safety, because Allah knows the tongues.”