Remembrance 16 from Chapter 51
What to say in the morning and the evening
Raḍītu bi-llāhi Rabbā, wa bi-l-Islāmi dīnā, wa bi-Muḥammadin—ṣalla-llāhu ‘alayhi wa-sallam—Nabiyyā.
We relate in the book of at-Tirmidhī that Thawbān 
reported that the Messenger of Allah 
said: “If a person says in the evening: I am pleased with Allah as Lord, with Islam as religion and with Muḥammad as Prophet, it will be an obligation for Allah to make him happy and pleased.” [17].Its isnād includes Sa‘īd ibn al-Marzubān Abū Sa‘d al-Baqqāl—with bā’—of Kūfa, who was the freed slave of Ḥudhayfah ibn al-Yamān and who is considered a weak narrator by all the major memorisers and authorities. At-Tirmidhī, however, considered this to be a ḥasan ṣaḥīḥ hadith which is unusual in this narration; so perhaps it was ṣaḥīḥ in his view from another narration.