Keeping Firm Upon Religion

O Changer of the hearts, make my heart firm upon Your religion
Shahr bin Hawshab said: “I said to Umm Salamah: ‘O Mother of the Believers! What was the supplication that the Messenger of Allah (ﷺ) said most frequently when he was with you?” She said: ‘The supplication he said most frequently was: “O Changer of the hearts, make my heart firm upon Your religion (Yā Muqallibal-qulūb, thabbit qalbī `alā dīnik).’”