The word(s) "heart" appears 171 time(s) in 159 verse(s) in Quran in Muhammad Habib Shakir translation.

(121) Have you then considered him who takes his low desire for his god, and Allah has made him err having knowledge and has set a seal upon his ear and his heart and put a covering upon his eye. Who can then guide him after Allah? Will you not then be mindful?

(122) And certainly We had established them in what We have not established you in, and We had given-- them ears and eyes and hearts, but neither their ears, nor their eyes, nor their hearts availed them aught, since they denied the communications of Allah, and that which they mocked encompassed them.

(123) And there are those of them who seek to listen to you, until when they go forth from you, they say to those who have been given the knowledge: What was it that he said just now? These are they upon whose hearts Allah has set a seal and they follow their low desires.

(124) And those who believe say: Why has not a chapter been revealed? But when a decisive chapter is revealed, and fighting is mentioned therein you see those in whose hearts is a disease look to you with the look of one fainting because of death. Woe to them then!

(125) Do they not then reflect on the Quran? Nay, on the hearts there are locks.

(126) Or do those in whose hearts is a disease think that Allah will not bring forth their spite?

(127) He it is Who sent down tranquillity into the hearts of the believers that they might have more of faith added to their faith-- and Allah's are the hosts of the heavens and the earth, and Allah is Knowing, Wise--

(128) Those of the dwellers of the desert who were left behind will say to you: Our property and our families kept us busy, so ask forgiveness for us. They say with their tongues what is not in their hearts. Say: Then who can control anything for you from Allah if He intends to do you harm or if He intends to do you good; nay, Allah is Aware of what you do:

(129) Nay! you rather thought that the Apostle and the believers would not return to their families ever, and that was made fairseeming to your hearts and you thought an evil thought and you were a people doomed to perish.

(130) Certainly Allah was well pleased with the believers when they swore allegiance to you under the tree, and He knew what was in their hearts, so He sent down tranquillity on them and rewarded them with a near victory,