The word(s) "hearts" appears 159 time(s) in 147 verse(s) in Quran in Abdullah Yusuf Ali translation.

(131) Thou wilt not find any people who believe in Allah and the Last Day, loving those who resist Allah and His Messenger, even though they were their fathers or their sons, or their brothers, or their kindred. For such He has written Faith in their hearts, and strengthened them with a spirit from Himself. And He will admit them to Gardens beneath which Rivers flow, to dwell therein (for ever). Allah will be well pleased with them, and they with Him. They are the Party of Allah. Truly it is the Party of Allah that will achieve Felicity.

(132) It is He Who got out the Unbelievers among the People of the Book from their homes at the first gathering (of the forces). Little did ye think that they would get out: And they thought that their fortresses would defend them from Allah! But the (Wrath of) Allah came to them from quarters from which they little expected (it), and cast terror into their hearts, so that they destroyed their dwellings by their own hands and the hands of the Believers, take warning, then, O ye with eyes (to see)!

(133) But those who before them, had homes (in Medina) and had adopted the Faith,- show their affection to such as came to them for refuge, and entertain no desire in their hearts for things given to the (latter), but give them preference over themselves, even though poverty was their (own lot). And those saved from the covetousness of their own souls,- they are the ones that achieve prosperity.

(134) And those who came after them say: "Our Lord! Forgive us, and our brethren who came before us into the Faith, and leave not, in our hearts, rancour (or sense of injury) against those who have believed. Our Lord! Thou art indeed Full of Kindness, Most Merciful."

(135) Of a truth ye are stronger (than they) because of the terror in their hearts, (sent) by Allah. This is because they are men devoid of understanding.

(136) They will not fight you (even) together, except in fortified townships, or from behind walls. Strong is their fighting (spirit) amongst themselves: thou wouldst think they were united, but their hearts are divided: that is because they are a people devoid of wisdom.

(137) And remember, Moses said to his people: "O my people! why do ye vex and insult me, though ye know that I am the messenger of Allah (sent) to you?" Then when they went wrong, Allah let their hearts go wrong. For Allah guides not those who are rebellious transgressors.

(138) That is because they believed, then they rejected Faith: So a seal was set on their hearts: therefore they understand not.

(139) He knows what is in the heavens and on earth; and He knows what ye conceal and what ye reveal: yea, Allah knows well the (secrets) of (all) hearts.

(140) If ye two turn in repentance to Him, your hearts are indeed so inclined; But if ye back up each other against him, truly Allah is his Protector, and Gabriel, and (every) righteous one among those who believe,- and furthermore, the angels - will back (him) up.