The New Life (Covenant).

LORD GOD:
"For THE LIFE of the flesh is in the blood: and I HAVE GIVEN IT TO YOU upon the altar to make an atonement for your souls: for it is the blood that maketh an atonement for the soul." (Lev 17:11), and 

Christ Jesus:
"And he took bread, and gave thanks, and brake it, and gave unto them, saying, THIS IS MY BODY WHICH IS GIVEN FOR YOU: this do in remembrance of me." (Luke 22:19)

[IMPORTANT: Incase you still don't KNOW or in doubt, the LORD God in the old testament IS THE SAME Christ Jesus in the new testament. If you still have doubts, then you still do not have the faith to receive of His life.]

The Eternal Life: Verily, Verily, INDEED. 
"Then Jesus said unto them, VERILY, VERILY, I say unto you, Except ye eat the flesh of the Son of man, and drink his blood, ye have no life in you. Whoso eateth my flesh, and drinketh my blood, hath eternal life; and I will raise him up at the last day. For my flesh is meat indeed, and my blood is drink INDEED." (Joh 6:53-55)

Eternal Life is the regular consumption of the Body (Flesh and Blood) of Jesus Christ, and the resurrection of our bodies totally hinges on this.

1- The Living Bread.
"I Am the living bread which came down from heaven: if any man eat of this bread, he shall live for ever: and THE BREAD THAT I WILL GIVE IS MY FLESH, which I will give for THE LIFE of the world." (John 6:51) ...  Isn't this what John 3:16 is saying?!

2- The Blood.
"And he took the cup, and gave thanks, and gave it to them, saying, Drink ye all of it; For this is my blood of the new testament, which is shed for many for the remission of sins." (Mat 26:27-28) ... Isn't this our own "passover blood"?!

Partakers Of The New Life.
The Blood of Christ carries His kind of life (i.e., Eternal Life), and as we eat His flesh and drink His blood, there is a transference of His kind of life into us. And without faith, this communion becomes a religious act, lacking in the eternal life of Christ. You MUST believe the bread IS the equivalent of the flesh of Christ, and the drink IS the equivalent of the Blood of Christ. As the bread and drink is blessed and served from the altar, IT'S HAS BECOME CHRIST'S.

"For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life." (John 3:16) 

Right in the very presence of His disciples, Christ demonstrated faith by turning the bread and drink supernaturally into His Body: Flesh and Blood (Mat 26:26-29). There's no other way around this, you MUST believe the same way the disciples did. Nothing has changed in the way of drawing the eternal life of Christ into our own bodies.