The Supersoul is God’s expansion within our hearts.
The Vedic sages distinguish between the Supersoul and the small individual soul. Both reside within the heart, but one is infinite, the other infinitesimal. The soul, the tiny spark of consciousness within, is our true self—eternal, blissful, and wise. But it is small, and so it may get lost in illusion and entangled in material life.
But the Supersoul, great and infinite, is ever beyond illusion.