Prophet Muhammad(ﷺ) is reported to have said “there is a piece of flesh in the body if it becomes good (reformed) the whole body becomes good but if it gets spoiled, the whole body gets spoiled – and that is the heart” (Bukhari)
Also Aisha (ra) reports that “when the Apostle of Allah (pbuh) awake at night, he said: There is no God but Thou, glory be to Thee, O Allah, I ask Thy pardon for my sin and I ask Thee for Thy mercy. O Allah! advance me in knowledge: do not cause my heart to deviate (from guidance) after Thou hast guided me, and grant me mercy from thyself; verily thou art the grantor.” (Bukhari)
Biologically speaking, we know that the heart is the most important organ in our body. If the blood supply is cut from reaching the brain we can suffer a stroke, likewise if the blood fails to reach certain limbs of our body those limbs will start decaying.
What is important to note is that, even in your personality the heart is also the most important organ. It can lead to a person being good morally, emotionally and spiritually. The heart responds faster than the brain hence you find that in human beings, there tends to be firstly, a display of emotional responses rather than logical ones. The reason for this is because the heart has the capacity to control our emotions.
Allah refers to the heart in a special way in Surah Al Mu’min;
“Warn them of the Day that is (ever) drawing near, when the hearts will (come) right up to the throats to choke (them); no intimate friend nor intercessor will the wrong-doers have, who could be listened to”. (40:18)
Allah is not referring to the physical heart but instead all the emotions that are generated from the heart. Man would be one that Day ‘dumb-founded’, in a state of shock, awe and every other possible emotion. All these emotions come from the heart and not the brain as some believe.
Again Allah says in Surah Ar Ra’d
“Those who believe, and whose hearts find satisfaction in the remembrance of Allah; for, without doubt; in the remembrance of Allah do hearts find satisfaction.” (13:28)
Stress, peace, tranquillity; etc. they all come from the heart and Allah is the One Who will put peace and comfort in the heart. And with reference to the ayat quoted above; engaging in His remembrance will lead to ones heart attaining satisfaction.
Allah also makes mention of the different categories of people whose hearts are concealed;
In their hearts is a disease; and Allah has increased their disease: and grievous is the penalty they (incur), because they are false (to themselves). (2:10)
It us He who sends down tranquillity in the hearts of men
It is He who sent down tranquillity into the hearts of the believers, that they may add Faith to their faith; – for to Allah belong the forces of the heavens and the earth; and Allah is full of knowledge and Wisdom (48:4)
The best thing one can have is a peaceful heart and engaged in non-beneficial things. Through this you will understand the meaning of Surah Naas
from the mischief of the Whisperer (of Evil), who withdraws (after His whisper), (the same) who whispers into the hearts of mankind, among Jinns and among men.
The heart controls out intentions and our emotions. It is a truly important dimension of the personality. This is a vast topic and much more can be said of it. Always remember to fill your heart with peace and love, and insha Allah, Allah will keep any ‘disease’ away from the heart.
We beg Him to guide us and to bless our hearts just as our beloved Messenger use to pray. And may He keep us far away from those thoughts, actions and emotions that can lead to our hearts becoming hard and concealed.