Ubayy ibn Ka’b reported: I said, “O Messenger of Allah, I send blessings upon you often. How many of my prayers should be for blessings upon you?” The Prophet said, “As you wish.” I said, “A fourth?” The Prophet said, “As you wish, but more is better for you.” I said, “A half?” The Prophet said, “As you wish, but more is better for you.” I said, “Two-thirds?” The Prophet said, “As you wish, but more is better for you.” I said, “Should I say all of my prayers for blessings upon you?” The Prophet said, “If so, your worries will be resolved, and your sins will be forgiven.”
Source: Sunan al-Tirmidhī 2457
Grade: Hasan (fair) according to Al-Tirmidhi
عَنْ أُبَيِّ بْنِ كَعْبٍ قُلْتُ يَا رَسُولَ اللَّهِ إِنِّي أُكْثِرُ الصَّلَاةَ عَلَيْكَ فَكَمْ أَجْعَلُ لَكَ مِنْ صَلَاتِي فَقَالَ مَا شِئْتَ قُلْتُ الرُّبُعَ قَالَ مَا شِئْتَ فَإِنْ زِدْتَ فَهُوَ خَيْرٌ لَكَ قُلْتُ النِّصْفَ قَالَ مَا شِئْتَ فَإِنْ زِدْتَ فَهُوَ خَيْرٌ لَكَ قُلْتُ فَالثُّلُثَيْنِ قَالَ مَا شِئْتَ فَإِنْ زِدْتَ فَهُوَ خَيْرٌ لَكَ قُلْتُ أَجْعَلُ لَكَ صَلَاتِي كُلَّهَا قَالَ إِذًا تُكْفَى هَمَّكَ وَيُغْفَرُ لَكَ ذَنْبُكَ
2457 سنن الترمذي كتاب صفة القيامة والرقائق والورع باب منه
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