John 6

In the Savior's ministry, there arrived a point where there was a need to begin to seperate the wheat from the tares, or in other words, those that followed the Savior because of His miracles and those that believed His doctrine. For there were those that upon witnessing, or maybe you could say even entertained by his miracles -

"...perceived that they would come and take him by force, to make him a king..." (New Testament | John 6:15)

Their vision was only of deliverence from the Roman control of their day. It was after this following that the Savior declared -

"...I am the bread of life: he that cometh to me shall never hunger; and he that believeth on me shall never thirst." (New Testament | John 6:35)

"For the bread of God is he which cometh down from heaven, and giveth life unto the world." (New Testament | John 6:33)

And then using an analogy that this people clearly understood taught -

"This is the bread which cometh down from heaven, that a man may eat thereof, and not die.
51 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." (New Testament | John 6:50 - 51)

"Except ye eat the flesh of the Son of man, and drink his blood, ye have no life in you.
54 Whoso eateth my flesh, and drinketh my blood, hath eternal life; and I will raise him up at the last day.
55 For my flesh is meat indeed, and my blood is drink indeed." (New Testament | John 6:53 - 55)

Elder Bruce R. McConkie commented -

"I am the bread of everlasting life, even that spiritual bread of which men must eat to gain everlasting life. This spiritual bread is that which cometh down from heaven, that a man may eat thereof and not die spiritually, which spiritual death is to be cast out of the presence of the Lord and to die as pertaining to things of righteousness. True, your fathers did eat manna in the wilderness, but they are dead, for this manna satisfied their temporal hunger only; it was not that spiritual bread of which men may eat and gain spiritual or eternal life. But I am the living bread, even the Son of God who came down from the Father in heaven. If any man shall eat of this spiritual bread, he shall live forever in that, being born again, he shall be spiritually alive in this world and inherit eternal life, which is spiritual life in the presence of the Father, in the world to come. And to eat the living bread is to accept me as the Son of God and to obey my commandments. And this living bread, which I shall give unto all who believe in me and obey my law, is my own flesh, in that it shall be because of my atoning sacrifice and temporal death that men shall have power to eat of the living bread and gain eternal life. Therefore say I unto you, I will give my flesh for the life of the world." (DNTC 1:356-57.)

Such doctrine reminds me of the fruit or meat of the Tree of Life -

"...Come unto me and ye shall partake of the fruit of the tree of life; yea, ye shall eat and drink of the bread and the waters of life freely;"
(Book of Mormon | Alma 5:34)

With this doctrine -

"...many of his disciples went back, and walked no more with him." (New Testament | John 6:66)

This same symbolism was later introduced as an ordinance at that last supper. I believe this doctrine is critical in our worship in our day, that of humbly, worthily, and in repententace weekly partaking of the sacrament or the flesh and blood of the Savior.