On the authority of Abu Umayr Ibn Anas (RA) there is a hadith narrated by one of his Ansari uncles. He said, the Prophet (PBUH) was concerned about how to gather the people for prayer. Seeing that, someone suggested that a flag should be flown when it is time for prayer. Seeing that, they will inform each other. Rasulullah (SAW) did not like that. Some suggested that trumpets be sounded like the Jews. Rasulullah (SAW) did not like that either. Because the custom was Jewish. When some suggested the use of bells, he said, 'That is the custom of Christians.'
Abdullah Ibn Zayd (R.A.) departed bearing in mind the thoughts of Rasulullah (S.A.W.) on the matter. Then (by Allah) he was taught the call to prayer in a dream. The next morning he went to Rasulullah (s.a.w.) and informed him of the matter, saying, 'O Messenger of Allah, I was a little drowsy. At that time a stranger came and taught me the call to prayer.
Similarly, Umar Khattab (R.A.) also learned the azaan in a dream 20 days ago. But he kept it a secret. Then (after narrating the dream of Abdullah Ibn Zayd) he also told the Prophet (PBUH) about his dream.
The Prophet (PBUH) said, 'Why didn't you tell me earlier?'
Omar Khattab (RA) said, 'Abdullah Ibn Zayd told me about this before. I am ashamed of this.'
Rasulullah (SAW) said, 'Bilal, get up. Do as Abdullah Ibn Zayd instructs you.'
Then Bilal (RA) gave the call to prayer. Abu Bishar said, 'Abu Umair (RA) narrated to me, the idea of ​​the Ansar – if Abdullah Ibn Zayd (RA) had not been ill that day, the Messenger of Allah (PBUH) would have appointed him as the muezzin.' (Sunan Abu Dawud, Hadith: 498)
