Krishna's physical form, his voice, his music are like the waves. His soul, hidden inside the body is like the ocean. Waves come and go, but the ocean is everlasting. While the forms of existence change, the soul, the spirit which abides in its élan vital is eternal. The Atma was there even when the Krishna in wave form was not born and the same Atma is there when the krshna in wave form is not here. It was there before our birth and it will be there even after our death also. Krishna is like a wave that arose from the oceanic form, appeared in Mathura, enchanted yashodha, loved radha, danced with gopis, delivered geeta, orchestrated gurushetra and become one with the same ocean.
If we look at our selves , we can also identify the existence of this two levels -- one at the level of waves and another at the level of the ocean. As waves we are individual human beings, and as the ocean we are also the supreme being or krshna.
All of us are also Krishna, but there is one difference. When Krishna is dancing as a wave he is aware that he belongs to the ocean, he is the ocean itself. But as far as we are concerned we know ourselves only as waves; we do not have the awareness of our oceanic. we forget that we are also the ocean. This is the difference between us and Krishna. And since we know ourselves only as waves, we fail to understand the oceanic form of Krishna.