وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ أَبَا هُرَيْرَةَ، كَانَ يَقُولُ إِذَا أَصْبَحَ وَقَدْ مُطِرَ النَّاسُ مُطِرْنَا بِنَوْءِ الْفَتْحِ ثُمَّ يَتْلُو هَذِهِ الآيَةَ ‏{‏مَا يَفْتَحِ اللَّهُ لِلنَّاسِ مِنْ رَحْمَةٍ فَلاَ مُمْسِكَ لَهَا وَمَا يُمْسِكْ فَلاَ مُرْسِلَ لَهُ مِنْ بَعْدِهِ ‏}‏

Yahya related to me from Malik that he had heard that Abu Hurayraused to say, when morning came after it had rained on the people, "Wehave been rained upon by the rain of Allah's opening," and would thenrecite the ayat, "Whatever Allah opens to man of His mercy no-one canwithhold, and whatever He withholds no-one can send forward after Him." (Sura 35 ayat 2). Translation Not Available

Book Ref: Muwatta Imam Malik Book 13 Hadith 457
Web Ref:  Muwatta Imam Malik Book 13 Hadith 6