The word(s) "hearts" appears 132 time(s) in 121 verse(s) in Quran in Mohsin Khan translation.

(41) It is only those who believe not in Allah and the Last Day and whose hearts are in doubt that ask your leave (to be exempted from Jihad). So in their doubts they waver.

(42) As-Sadaqat (here it means Zakat ) are only for the Fuqara' (poor), and Al-Masakin (the poor) and those employed to collect (the funds), and to attract the hearts of those who have been inclined (towards Islam), and to free the captives, and for those in debt, and for Allah's Cause (i.e. for Mujahidun - those fighting in a holy battle), and for the wayfarer (a traveller who is cut off from everything); a duty imposed by Allah. And Allah is All-Knower, All-Wise.

(43) The hypocrites fear lest a Surah (chapter of the Qur'an) should be revealed about them, showing them what is in their hearts. Say: "(Go ahead and) mock! But certainly Allah will bring to light all that you fear."

(44) So He punished them by putting hypocrisy into their hearts till the Day whereon they shall meet Him, because they broke that (covenant with Allah) which they had promised to Him and because they used to tell lies.

(45) They are content to be with those (the women) who sit behind (at home). Their hearts are sealed up (from all kinds of goodness and right guidance), so they understand not.

(46) The ground (of complaint) is only against those who are rich, and yet ask exemption. They are content to be with (the women) who sit behind (at home) and Allah has sealed up their hearts (from all kinds of goodness and right guidance) so that they know not (what they are losing).

(47) The building which they built will never cease to be a cause of hypocrisy and doubt in their hearts unless their hearts are cut to pieces. (i.e. till they die). And Allah is All-Knowing, All-Wise.

(48) Allah has forgiven the Prophet (صلى الله عليه وسلم), the Muhajirun (Muslim emigrants who left their homes and came to Al-Madinah) and the Ansar (Muslims of Al-Madinah) who followed him (Muhammad صلى الله عليه وسلم) in the time of distress (Tabuk expedition), after the hearts of a party of them had nearly deviated (from the Right Path), but He accepted their repentance. Certainly, He is unto them full of Kindness, Most Merciful.

(49) But as for those in whose hearts is a disease (of doubt, disbelief and hypocrisy), it will add suspicion and doubt to their suspicion, disbelief and doubt; and they die while they are disbelievers.

(50) And whenever there comes down a Surah (chapter from the Qur'an), they look at one another (saying): "Does any one see you?" Then they turn away. Allah has turned their hearts (from the light) because they are a people that understand not.