Holy Prophet(pbuh) - Selected Sayings

Now, let me also make it known that the very first thing you are rewarded with, after having completely submitted yourself to the instructions and teachings of the Holy Prophet Muhammad, is that you are granted a new heart which is always rightly inclined, that is to say, a heart which has turned cold upon the love of this material world, and instead it begins to yearn for an everlasting heavenly pleasure. Having achieved this desire, this heart is now fit to receive that perfect and purest love--the love of God. Because of your complete obedience to him, all these blessings are bequeathed to you as his spiritual heritage. [Roohani Khaza'in, Vol. 22: Haqeeqatul Wahi, pp. 64-65]