The word(s) "hearts" appears 130 time(s) in 121 verse(s) in Quran in Muhammad Pickthal translation.

(31) They only are the (true) believers whose hearts feel fear when Allah is mentioned, and when His revelations are recited unto them they increase their faith, and who trust in their Lord;

(32) Allah appointed it only as good tidings, and that your hearts thereby might be at rest. Victory cometh only by the help of Allah. Lo! Allah is Mighty, Wise.

(33) When He made the slumber fall upon you as a reassurance from him and sent down water from the sky upon you, that thereby He might purify you, and remove from you the fear of Satan, and make strong your hearts and firm (your) feet thereby.

(34) When thy Lord inspired the angels, (saying): I am with you. So make those who believe stand firm. I will throw fear into the hearts of those who disbelieve. Then smite the necks and smite of them each finger.

(35) When the hypocrites and those in whose hearts is a disease said: Their religion hath deluded these. Whoso putteth his trust in Allah (will find that) lo! Allah is Mighty, Wise.

(36) That is because Allah never changeth the grace He hath bestowed on any people until they first change that which is in their hearts, and (that is) because Allah is Hearer, Knower.

(37) And (as for the believers) hath attuned their hearts. If thou hadst spent all that is in the earth thou couldst not have attuned their hearts, but Allah hath attuned them. Lo! He is Mighty, Wise.

(38) O Prophet! Say unto those captives who are in your hands: If Allah knoweth any good in your hearts He will give you better than that which hath been taken from you, and will forgive you. Lo! Allah is Forgiving, Merciful.

(39) How (can there be any treaty for the others) when, if they have the upper hand of you, they regard not pact nor honour in respect of you? They satisfy you with their mouths the while their hearts refuse. And most of them are wrongdoers.

(40) And He will remove the anger of their hearts. Allah relenteth toward whom He will. Allah is Knower, Wise.