The Prophet (ﷺ) was concerned about how to gather the people for prayer. It was said to him, "Set up a banner when the time for prayer comes, and when they see it, they will inform one another." But he did not like that.
Then the qunq—meaning the shabur—was mentioned to him (and Ziyad said: The shabur of the Jews), but he did not like that and said, "This is a matter of the Jews."
Then the naqus (bell) was mentioned to him, and he said, "This is a matter of the Christians."
Then Abdullah ibn Zayd ibn Abd Rabbihi departed, deeply concerned about the concern of the Messenger of Allah (ﷺ), and he was shown the call to prayer in his sleep. He went early the next morning to the Messenger of Allah (ﷺ) and informed him, saying, "O Messenger of Allah, while I was between sleeping and wakefulness, someone came to me and showed me the call to prayer."
Umar ibn al-Khattab (may Allah be pleased with him) had already seen it before that, but he kept it hidden for twenty days. Then he informed the Prophet (ﷺ), who said to him, "What prevented you from informing me?" He replied, "Abdullah ibn Zayd beat me to it, and I felt shy."
The Messenger of Allah (ﷺ) said, "O Bilal, get up and see what Abdullah ibn Zayd tells you to do, and do it." So Bilal gave the call to prayer.
Abu Bishr said: Abu Umayr informed me that the Ansar believed that had Abdullah ibn Zayd not been ill on that day, the Messenger of Allah (ﷺ) would have made him the mu'adhdhin.