This is a strange hadith; we do not know it except through this chain, and its chain of transmission is not strong.

Chapter 140

3904 – ‘Uqbah ibn Mukram narrated to us, he said: Sa‘īd ibn Sufyān al-Jahdarī narrated to us, he said: ‘Abd Allāh ibn Ma‘dān narrated to us, he said: ‘Āṣim ibn Kulayb al-Jarmī informed me, from his father, from his grandfather, who said: I entered upon the Prophet, peace and blessings be upon him, while he was praying. He had placed his left hand on his left thigh and his right hand on his right thigh, and he clenched his fingers and extended the index finger, while saying: "O Turner of hearts, make my heart firm upon Your religion."

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= Via the chain of ‘Abd al-Wāḥid ibn Ziyād, from ‘Abd al-Raḥmān ibn Isḥāq, from a man of Quraysh, from Ibn ‘Ukaym, from ‘Umar ibn al-Khaṭṭāb, with it in abbreviated form.
This chain is also weak due to the anonymity of the Qurayshī man, and due to the weakness of ‘Abd al-Raḥmān ibn Isḥāq — who is Abū Shaybah al-Kūfī al-Wāsiṭī — and it is possible that he is the same Abū Shaybah mentioned in the chain of the compiler.

(1) Its chain is good.
It was also recorded by Ibn Qāni‘ in "Mu‘jam al-Ṣaḥābah" 1/337, al-Ṭabarānī in "al-Kabīr" (7233), Ibn ‘Adī in "al-Kāmil" 6/2252, and al-Mizzī in "Tahdhīb al-Kamāl" 12/577 via two chains from ‘Abd Allāh ibn Ma‘dān, with this chain.
Regarding the chapter of his supplication, peace and blessings be upon him: "O Turner of hearts, make my heart firm upon Your religion" — from Anas ibn Mālik, it has preceded with the compiler under number (2277), and it is a good hadith.
And from al-Nawwās ibn Sim‘ān, [it is recorded] with Aḥmad in "al-Musnad" under number (17630), and it is =