The word(s) "hearts" appears 136 time(s) in 127 verse(s) in Quran in Muhammad Habib Shakir translation.

(31) These towns-- We relate to you some of their stories, and certainly their apostles came to them with clear arguments, but they would not believe in what they rejected at first; thus does Allah set a seal over the hearts of the unbelievers

(32) And certainly We have created for hell many of the jinn and the men; they have hearts with which they do not understand, and they have eyes with which they do not see, and they have ears with which they do not hear; they are as cattle, nay, they are in worse errors; these are the heedless ones.

(33) Those only are believers whose hearts become full of fear when Allah is mentioned, and when His communications are recited to them they increase them in faith, and in their Lord do they trust.

(34) And Allah only gave it as a good news and that your hearts might be at ease thereby; and victory is only from Allah; surely Allah is Mighty, Wise.

(35) When He caused calm to fall on you as a security from Him and sent down upon you water from the cloud that He might thereby purify you, and take away from you the uncleanness of the Shaitan, and that He might fortify your hearts and steady (your) footsteps thereby.

(36) When your Lord revealed to the angels: I am with you, therefore make firm those who believe. I will cast terror into the hearts of those who disbelieve. Therefore strike off their heads and strike off every fingertip of them.

(37) And obey Allah and His Apostle and do not quarrel for then you will be weak in hearts and your power will depart, and be patient; surely Allah is with the patient.

(38) When the hypocrites and those in whose hearts was disease said: Their religion has deceived them; and whoever trusts in Allah, then surely Allah is Mighty, Wise.

(39) And united their hearts; had you spent all that is in the earth, you could not have united their hearts, but Allah united them; surely He is Mighty, Wise.

(40) O Prophet! say to those of the captives who are in your hands: If Allah knows anything good in your hearts, He will give to you better than that which has been taken away from you and will forgive you, and Allah is Forgiving, Merciful.