Our souls are the true Prajñāpāramitā. Originally the soul is the same as Prajñāpāramitā; there's no difference. Hes has the same great wisdom. Hes himself is the great wisdom, the great Tao, the original Self, and Buddha nature. However, when hes comes to this samsara world, hes is enveloped by many things and forgets hirs original Self.
A Mahasattva can help us to gradually take off the thick and heavy clothes on us layer by layer, then we can also see our original Self later.
Therefore, the most important thing is to meet a Mahasattva and learn the method from hirm. We should invite hirm to teach us the Tao or way that leads us back home, or go beyond the three worlds and liberate us from life and death. This is the sole duty of Mahasattva, which is to guide us beyond the three worlds and to be liberated from life and death.