Hisn al-Muslim
Book 1: Fortress of the Muslim (Hisn al-Muslim)
حصن المسلم
268 hadith in this book
The Prophet (ﷺ) said: The best invocation is that of the Day of Arafat, and the best that anyone can say is what I and the Prophets before me have said: Lā 'ilāha 'illallāhu waḥdahu lā sharīka lahu, lahul-mulku wa lahul-ḥamdu wa huwa `alā kulli shay'in qadīr. None has the right to be worshipped but Allah Alone, Who has no partner. His is the dominion and His is the praise, and He is Able to do all things. Reference: At-Tirmidhi. Al-Albani graded it good in Sahih At-Tirmidhi 3/184, and also Silsilatul-'Ahadith As-Sahihah 4/6.
خير الدعاء دعاء يوم عرفة ، وخيرُ ما قلت أنا والنبيُّون من قبلي : لا إله إلا الله وحدهُ لا شريك لهُ ، لهُ الملكُ ولهُ الحمدُ وهو على كل شيء قدير.
Hadith text, translations and grading are courtesy of Sunnah.com.