To prevent the heart’s crookedness
رَبَّنَا لا تُزِغْ قُلُوبَنَا بَعْدَ إِذْ هَدَيْتَنَا وَهَبْ لَنَا مِنْ لَدُنْكَ رَحْمَةً إِنَّكَ أَنْتَ الْوَهَّابُ
“Our Lord! Let not our hearts deviate (from the truth) after You have guided us and grant us mercy from You. Truly, You are the Bestower.” (Al-Imran 3:8)
For the heart’s illumination
اللَّهُمَّ اجْعَلْ فِي قَلْبِي نُورًا
“Oh Allah! Create light in my heart.” (Bukhari)
For the heart’s guidance
رَبِّ تَقَبَّلْ تَوْبَتِي وَاغْسِلْ حَوْبَتِي وَأَجِبْ دَعْوَتِي وَثَبِّتْ حُجَّتِي وَاهْدِ قَلْبِي وَسَدِّدْ لِسَانِي وَاسْلُلْ سَخِيمَةَ قَلْبِي
“My Lord, accept my repentance, wash away my sin, answer my supplication, clearly establish my evidence, guide my heart, make true my tongue and draw out malice in my breast.” (Abu Dawood)
For the heart’s steadfastness
اللَّهُمَّ مُصَرِّفَ الْقُلُوبِ صَرِّفْ قُلُوبَنَا عَلَى طَاعَتِكَ
“O Allah! O Turner of the hearts, turn our hearts to your obedience.” (Muslim)
For the heart’s Taqwa
اللَّهُمَّ آتِ نَفْسِي تَقْوَاهَا وَزَكِّهَا أَنْتَ خَيْرُ مَنْ زَكَّاهَا أَنْتَ وَلِيُّهَا وَمَوْلاَهَا
“O Allah! Grant piety to my soul and purify it. You are the best to purify it and you are its Helper and Master.” (Muslim)