Muwatta Malik, Book 10, Hadith 441 (In-Book)

Yahya related to me from Malik that he had heard that Said ibn al-Musayyab used to go to the place of prayer after praying subh, and before the sun rose.

وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ سَعِيدَ بْنَ الْمُسَيَّبِ، كَانَ يَغْدُو إِلَى الْمُصَلَّى بَعْدَ أَنْ يُصَلِّيَ الصُّبْحَ قَبْلَ طُلُوعِ الشَّمْسِ ‏.‏

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also referenced under: Book 10, Hadith 11 (USC-MSA)