Mishkat al-Masabih 1 Faith كتاب الإيمان 95

وَعَنْ أَنَسٍ قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يُكْثِرُ أَنْ يَقُولَ: «يَا مُقَلِّبَ الْقُلُوبِ ثَبِّتْ قَلْبِي عَلَى دِينِكَ» فَقُلْتُ: يَا نَبِيَّ اللَّهِ آمَنَّا بِكَ وَبِمَا جِئْتَ بِهِ فَهَلْ تَخَافُ عَلَيْنَا؟ قَالَ: «نَعَمْ إِنَّ الْقُلُوبَ بَيْنَ أُصْبُعَيْنِ مِنْ أَصَابِعِ اللَّهِ يُقَلِّبُهَا كَيْفَ يَشَاءُ» . رَوَاهُ التِّرْمِذِيّ وَابْن مَاجَه

Anas reported that God’s messenger often said, “O Thou who turnest the hearts about, establish my heart in Thy religion.” Anas said, “Prophet of God, do you fear for us who believe in you and in your message?” He replied, “Yes. The hearts are between two of God’s fingers and He turns them about as He wills.” Tirmidhi and Ibn Majah transmitted it.