It is narrated from Sayyiduna Anas (may Allah be pleased with him) that Sayyiduna Abu Bakr (may Allah be pleased with him) led us in the Subh prayer and recited Al Imran; the sun was about to rise. He said: Had it risen, it would not have found us heedless.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 1779