Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) narrates that the Noble Prophet (peace and blessings be upon him) said: Let not Bilal’s call to prayer prevent you from eating the pre-dawn meal (suhoor), for he gives the call to prayer during the night, or (he said) he calls so that those who are awake for worship may return to rest, and those who are still asleep may become alert. No one should think that dawn or true dawn (subh sadiq) has occurred. And the Prophet (peace and blessings be upon him) demonstrated the state of the rising of dawn with his fingers: he raised his fingers upward and then slowly brought them down, and then said: This is how (the dawn) appears.
Hadith Referenceاللؤلؤ والمرجان / كتاب الصيام / 664
Hadith Gradingمحدثین:«صحیح»
Hadith Takhrij«صحیح، أخرجه البخاري في: 10 كتاب الأذان: 13 باب الأذان قبل الفجر»