يَا مُقَلِّبَ الْقُلُوبِ ثَبِّتْ قَلْبِي عَلَى دِينِكَ
The most frequent supplication of the Prophet (peace be upon him) was: 'Ya Muqallibal-qulub, thabbit qalbi 'ala dinik.' I said: 'O Messenger of Allah, we believe in you and in what you have brought. Do you fear for us?' He said: 'Yes, for the hearts are between two fingers of Allah, He turns them however He wills.'