Bismi Allah ar-Rahman ar-Raheem
The Holy Prophet said: "In the body of man there is a piece of flesh. If it is healthy, the whole body is healthy. This piece of flesh is the heart." The heart is most important, as it is the seat of man's reality, of his personality and character. The heart's health depends on faith.
Health comes through sincerity, illness through hypocrisy. Health comes through love of Allah, illness through love of Dunya. Health comes through contentedness, illness through greed. Health comes through gentleness, illness though anger. Health comes through the remembrance of the Lord, Dhikr, illness through heedlessness, forgetting Allah. Health means being with Allah, illness means to forget Allah and to be with Shaitan. There are so many spiritual illnesses of the heart: Hypocrisy, Shirk(Polytheism), showing-off, pride, greed, envy, jealousy, hatred, stubborness, love of this world, egoism, lying, back-biting, bad intentions... Whoever has any of these characteristics is ill and in need of treatment.
The Prophet came to cure hearts. There was no illness, physical or spiritual, which he could not heal. He cured his Companions, the Sahabas, and raised them in rank, so that they became like stars in the sky. Then the Sahabas became doctors themselves and cured others. Those who followed them, the Tabiin, became healers, too, and so on until today.
Every Saint, inheritor of the Prophet, has the ability to give medicine to people for physical and spiritual illnesses. If anyone wants to know about the condition of his heart, he must go to someone who knows. But nowadays, people are so proud that they think they can cure themselves. They accept neither Saints, nor scholars, nor other people of knowledge. But even a chief-doctor calls another doctor for help when he is ill. He doesn't stand in front of a mirror and cure himself. And it is a Divine Order to consult those who are always in the Divine Presence, because the answers that come to their heart are sent to them by Allah Himself. Maulana Shaykh Nazim al Haqqani