Qalb, the heart, is for the Sufis not the seat of emotion but the centre where God is known. A hadith says that the heavens and earth cannot contain God, but the heart of the believer does. Remembrance polishes the heart of its rust until it reflects the divine.
Qalb
The heart: in Sufism, the spiritual organ of knowing God, which must be polished like a mirror.
Also: Qalb, heart