Here are 6 Bible verses about first Holy Communion from the Old and New Testaments of the Holy Bible (King James Version), sorted from most to least relevant.
John 6:35 KJV
And Jesus said unto them, I am the bread of life: he that cometh to me shall never hunger; and he that believeth on me shall never thirst.
John 6:31 KJV
Our fathers did eat manna in the desert; as it is written, He gave them bread from heaven to eat.
Matthew 19:14 KJV
But Jesus said, Suffer little children, and forbid them not, to come unto me: for of such is the kingdom of heaven.
John 6:51 KJV
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.
Matthew 26:26-28 KJV
And as they were eating, Jesus took bread, and blessed it, and brake it, and gave it to the disciples, and said, Take, eat; this is my body. 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.
John 15:5 KJV
I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing.