I came upon the Prophet ﷺ while he was praying. He had placed his left hand on his left thigh and his right hand on his right thigh, closed his fingers, and extended his index finger, saying, "Turner of hearts, keep my heart firm upon Your religion."
حدثنا عقبة بن مكرم حدثنا سعيد بن سفيان الجحدري حدثنا عبد الله بن معدان قال أخبرني
دخلت على النبي ﷺ وهو يصلي وقد وضع يده اليسرى على فخذه اليسرى ووضع يده اليمنى على فخذه اليمنى وقبض أصابعه وبسط السبابة وهو يقول يا مقلب القلوب ثبت قلبي على دينك
[Its chain is hasan]. Tabarani reported it (7/313, no. 7232) through Abdullah bin Madan, via him, and he is reliable, a group of narrators reported from him. The criticism attributed to Abu Dawud, may Allah have mercy on him, regarding this hadith is not established. The hadith has corroborating narrations from Anas, Jabir, and Nawas bin Saman