Sahih Bukhari · Hadith 6499
To make the Heart Tender (Ar-Riqaq) - كتاب الرقاق
قال سمعت عتبان بن مالك الأنصاري، ثم أحد بني سالم قال غدا على رسول الله صلى الله عليه وسلم فقال " لن يوافي عبد يوم القيامة يقول لا إله إلا الله. يبتغي به وجه الله، إلا حرم الله عليه النار ".
Narrated `Utban bin Malik Al-Ansari: who was one of the men of the tribe of Bani Salim: Allah's Apostle came to me and said, "If anybody comes on the Day of Resurrection who has said: La ilaha illal-lah, sincerely, with the intention to win Allah's Pleasure, Allah will make the Hell-Fire forbidden for him."
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).