Hadith 2679 a - The Book Pertaining to the Remembrance of Allah, Supplication, Repentance and Seeking Forgiveness - Sahih Muslim - صحيح مسلم - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

48. The Book Pertaining to the Remembrance of Allah, Supplication, Repentance and Seeking Forgiveness - كتاب الذكر والدعاء والتوبة والاستغفار

3) Chapter: Being Firm In Supplication And Not Saying: "If You Will"

Abu Huraira reported Allah's Messenger (ﷺ) as saying:

When one of you makes a supplication (to his Lord) one should not say: O Allah, grant me pardon, if Thou so likest, but one should beg one's (Lord) with a will and full devotion, for there is nothing so great in the eye of Allah which He cannot grant.

Reference: 2679 a
English reference: Book 35, Hadith 6478
In-book reference: Book 48, Hadith 8
Grade: Sahih
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3) باب الْعَزْمِ بِالدُّعَاءِ وَلاَ يَقُلْ إِنْ شِئْتَ

حَدَّثَنَا يَحْيَى بْنُ أَيُّوبَ، وَقُتَيْبَةُ، وَابْنُ، حُجْرٍ قَالُوا حَدَّثَنَا إِسْمَاعِيلُ، - يَعْنُونَ ابْنَ جَعْفَرٍ - عَنِ الْعَلاَءِ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏‏ ‏.‏ "‏ إِذَا دَعَا أَحَدُكُمْ فَلاَ يَقُلِ اللَّهُمَّ اغْفِرْ لِي إِنْ شِئْتَ وَلَكِنْ لِيَعْزِمِ الْمَسْأَلَةَ وَلْيُعَظِّمِ الرَّغْبَةَ فَإِنَّ اللَّهَ لاَ يَتَعَاظَمُهُ شَىْءٌ أَعْطَاهُ ‏"