Abdullah bin Umar reported,

The Messenger of Allah ﷺ had two muezzins, Bilal and Ibn Umm Maktum, who was blind. The Messenger of Allah ﷺ said, "Bilal calls the adhan at night, so eat and drink until Ibn Umm Maktum calls the adhan."The narrator said, "There was no interval between their two calls except for the time it took one to come down and the other to climb up."

Muslim 2538

Sahih

حدثنا ابن نمير حدثنا أبي حدثنا عبيد الله عن نافع

عن ابن عمر رضي الله عنهما قال

كان لرسول الله ﷺ مؤذنان بلال وابن أم مكتوم الأعمى فقال رسول الله ﷺ إن بلالا يؤذن بليل فكلوا واشربوا حتى يؤذن ابن أم مكتوم قال ولم يكن بينهما إلا أن ينزل هذا ويرقى هذا

مسلم 2538صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Fasting
Chapter
Clarification that entering into fasting occurs at the rising of Fajr, and that one may eat and otherwise until Fajr rises, and clarification of the description of Fajr to which rulings are attached regarding entering into fasting, the beginning of the time for the morning prayer, and other matters
Numbering
Darussalam 2538
Muslim 2538