Ishaq bin Mansur al-Kausaj إسحاق بن منصور بن بهرام - الكوسج · Chapters on Supplication

“The Messenger of Allah (ﷺ) said: ‘Whoever says when he reaches the evening: “I am pleased with Allah as (my) Lord, with Islam as (my) religion, and with Muhammad (ﷺ) as (my) Prophet (Raḍītu billāhi rabban wabil-Islāmi dīnan wa bi-Muḥammadin nabiyyan) it is a duty upon Allah to please him.’” (Hasan Gharib)