The word(s) "heart" appears 213 time(s) in 195 verse(s) in Quran in Abdullah Yusuf Ali translation.

(111) Those who reject Faith say: "Why is not the Qur'an revealed to him all at once? Thus (is it revealed), that We may strengthen thy heart thereby, and We have rehearsed it to thee in slow, well-arranged stages, gradually.

(112) "But only he (will prosper) that brings to Allah a sound heart;

(113) To thy heart and mind, that thou mayest admonish.

(114) Thus have We caused it to enter the hearts of the sinners.

(115) And verily thy Lord knoweth all that their hearts do hide. As well as all that they reveal.

(116) But there came to be a void in the heart of the mother of Moses: She was going almost to disclose his (case), had We not strengthened her heart (with faith), so that she might remain a (firm) believer.

(117) And thy Lord knows all that their hearts conceal and all that they reveal.

(118) Then there are among men such as say, "We believe in Allah"; but when they suffer affliction in (the cause of) Allah, they treat men's oppression as if it were the Wrath of Allah! And if help comes (to thee) from thy Lord, they are sure to say, "We have (always) been with you!" Does not Allah know best all that is in the hearts of all creation?

(119) Nay, here are Signs self-evident in the hearts of those endowed with knowledge: and none but the unjust reject Our Signs.

(120) And among His Signs is this, that He created for you mates from among yourselves, that ye may dwell in tranquillity with them, and He has put love and mercy between your (hearts): verily in that are Signs for those who reflect.