In Sabikalpa samadhi yoga,
You will drown yourself in your self.
In nirbikalpa samadhi yoga,
You will find yourself in yourself.
In sabikalpa samadhi yoga you will drown (melt) yourself (ego) in yourself (Spirit). In nirbikalpa samadhi yoga, you will find (see) yourself (ego) in yourself (spirit)
In sabikalpa samadhi the devotee attains temporary realization of his oneness with Spirit but cannot maintain his cosmic consciousness except in the immobile state. By continuous meditation he reaches the higher state of nirbikalpa samadhi, in which he may move freely in the world and perform his out ward duties without any loss of God perception. He realizes fully his idetity as spirit.
From Words of Cosmic Chants–
by Sri Paramahansa yoganada