صحیح ابن حبان
Ibn Hibban
كتاب الرقائق
Book of Heart-Softeners
باب الأذكار - ذكر البيان بأن الحمد لله جل وعلا من أفضل الدعاء والتهليل له من أفضل الذكر
Chapter on Remembrance – Explaining that praising Allah is among the best supplications, and declaring His oneness is among the best remembrance
1 hadith
Hadith 846
Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) narrates: I heard the Prophet (peace and blessings be upon him) say: "The best remembrance is «لا اله الا اللہ» and the best supplication is «الحمدللہ»."