The Prophet spoke about the heart in a manner that leads one to believe that its corruption means disaster for the soul and our happiness. “Purification” is not a state per se, as you will soon hear, but is a process and always so. It is called the “Greater Jihad” because the struggle never ends, so long as we live in this world. Our faith depends on winning this struggle, as does the kind of life we will meet in the Hereafter.
As the Prophet said, we all have a morsel of flesh in our bodies. If it is good, our whole is good and if it is not, then our whole body is spoiled. This hadith outlines a whole process of strengthening and purifying our hearts on the path to Allah: being alert to the halal and haram and avoiding the doubtful. The Prophet says in another hadith,
A person’s iman will not be upright until their heart is upright and strong. The heart will not be upright and strong until the tongue is upright and strong.
The Prophet is laying out the path to purifying and strengthening the heart, which leads to the completion of one’s faith.
