35.40 . Say : Have ye seen your partner gods to whom ye pray beside Allah? Show me what they created of the earth! Or have they any portion in the heavens? Or have We given them a Scripture so that they act on clear proof therefrom? Nay , the evil doers promise one another only to deceive .
The Prophet had a mat which he used to spread during the day and use as a curtain at night. So a number of people gathered at night facing it and prayed behind him.
Allah's Apostle made a small room in the month of Ramadan (Sa'id said, "I think that Zaid bin Thabit said that it was made of a mat") and he prayed there for a few nights, and so some of his companions prayed behind him. When he came to know about it, he kept on sitting. In the morning, he went out to them and said, "I have seen and understood what you did. You should pray in your houses, for the best prayer of a person is that which he prays in his house except the compulsory prayers."
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Volume:1 Book :11 (Call to Prayers (Adhaan))Number :697
Book: Call to Prayers (Adhaan) 
Book of Belief