“Let not the call to prayer of Bilāl, regarding your pre-dawn meal, deceive you, nor the vertical whiteness of the horizon like this, until it spreads like this.”

Narrated by Muslim (no. 1094), from the ḥadīth of Samurah ibn Jundub — may Allah be pleased with him.

Brief Explanation of the Hadith

Among the most important matters a Muslim must observe in acts of worship is knowing their proper times—among them, the time of abstaining from food in Ramadān, which marks the beginning and end of the fast. In this ḥadīth, the Prophet—may Allah’s peace and blessings be upon him—alerted the believers to two important issues related to the time of suḥūr (pre-dawn meal) and imsāk (abstaining before dawn).
The first point: not to be deceived by the call to prayer of Bilāl — may Allah be pleased with him — for he used to give the adhān before the true dawn. His call served as a reminder for those sleeping and an alert for those praying that dawn was near, not as an indication that the time for imsāk (abstaining from food and drink) had begun.
The actual time of imsāk is at the adhān of Ibn Umm Maktum — may Allah be pleased with him — who would not give the call to prayer until it was said to him, “Morning has come, morning has come,” meaning that the true dawn had appeared.
The second point: not to be deceived by the first whiteness that appears in the sky, rising vertically along the horizon, which is known as the false dawn. The Arabs used to call it “Dhanab al-Sirhān” — meaning the tail of the wolf — because its light extends upward like a column and does not spread horizontally across the horizon.
As for the true dawn, it is the whiteness that spreads horizontally along the horizon in the east. This marks the beginning of the time for Fajr prayer and the start of fasting. The Prophet — may Allah’s peace and blessings be upon him — described it by saying: “until it spreads like this,” meaning until its light extends across the horizon.
The ḥadīth provides a precise clarification of the distinction between the false dawn and the true dawn, and it instructs that fasting should not begin with the first call to prayer or the mere appearance of vertical light in the sky, but rather when the true dawn appears, spreading horizontally across the horizon.
It also indicates that there were two calls to prayer (adhāns) for Fajr in the time of the Prophet — may Allah’s peace and blessings be upon him — the first to alert those preparing for prayer or pre-dawn meal, and the second marking the actual entry of Fajr time.
The ḥadīth further affirms the tolerance and ease inherent in the Islamic Sharīʿah, particularly in its precise regulation and preservation of the appointed times for acts of worship.