To really understand, you have to go way back, before He was born to the virgin Mary over 2,000 years ago. One of His disciples, John, had this explanation revealed to him after he's seen the resurrected Jesus ascend bodily up to Heaven:
"In the beginning was the Word, and the Word was with God, and the Word was God. He was with God in the beginning.
All things were made through Him, and without Him nothing that was made was made.
In Him was life, and that life was the light of men. The light shines in the darkness but the darkness has not understood it.
He was in the world, and though the world was made through Him, the world did not recognize Him...
The Word became flesh and dwelt among us. We have seen His glory, that of the only-begotten who came from the Father, full of grace and truth...
No-one has ever seen God but the only-begotten Son, who is at the Father's side, has made Him known... the Lamb of God who takes away the sin of the world." John 1:1-29 (Please read the whole chapter to get the sense of this awesome revelation.)