Jesus told him that the wind blows where it wishes, and you can hear the sound of it but cannot tell where it comes from and where it goes. Flesh is flesh and Spirit is spirit. God breathed upon man and he became a living soul, Jesus breathed upon men that they might become living spirits. As He did so, He told them to receive. This involves a breathing in of that which was breathed out.
Breathing is an integral and necessary part of man.
He must breathe in order to live. He can, as he breathes the air into his lungs, see ,with the eye of faith, the Spirit surging through him, quickening every part of his being. He does not lie there stagnant within. It is a moving force, ever flowing like a mighty river as He, the Spirit of God moves in and through the Spirit-filled believer. Granted it takes constant attention in the beginning to establish this connection between breathing air into the lungs and Spirit into the inner being.