The wind blows where it wills, and you hear the sound thereof, but cannot tell from where it comes, and where it goes: so is every one that is born of the Spirit. (John 3:8)
The conversation Jesus had with Nicodemus is one with a man who had no frame of reference for the spiritual realm. Jesus tried to tell him, “Unless you are born from above you cannot see the kingdom of God.” (John 3:3) But he even interpreted this on a natural level. Finally, Jesus gives the above description to him of the nature of the new birth: It is a life you cannot see with the natural eye.
The new birth from above is the result of Jesus Christ, through the Spirit of God, joining us to Himself – His Spirit to our human spirit. This is the new creature in Christ Jesus. But the natural man cannot see the new creature in Christ – although the effects can be seen. The only way to see the new creation is to become one. This is why it is impossible to make people understand what it means to have an inward revelation of Jesus Christ. But once they begin to see Him, they will know exactly what you mean.