In the night of Meraj, the blessed heart of the Holy Prophet (Sallallahu alaihi wa sallam) was washed with Zam Zam. His bosom was opened. A receptacle full of Iman and wisdom was poured into it.
Life depends on the heart. Heart is the very center of life. There is no one in the universe who can stay alive without the heart. Even during heart surgeries, the doctors have to use machines which keep the patient alive. The opening of the bosom, the washing of His blessed heart, the pouring of wisdom and all this is related by the Holy Prophet (Sallallahu alaihi wa sallam) Himself.
Even after removal of the heart, the Holy Prophet (Sallallahu alaihi wa sallam) is alive. This shows even when the essentials of life are withdrawn, the life and the knowledge and understanding of the Holy Prophet (Sallallahu alaihi wa sallam) are unaffected.