John 6:51 I am the living bread which came down from heaven; if any one eats of this bread, he will live for ever; and the bread which I shall give for the life of the world is my flesh."
There are a lot of people who don't know why the Lord's Supper is important. Because they don't know why its important, they tend to neglect it, as we often do with things we don't understand. Part of it may be things we have heard in the past, and remembered only in part. For example there are a number of people who believe that the Lord's Supper is something they only need to do 3 or 4 times a year - chances are they heard something in Catechism which went - "if anyone does not seek or desire the Lordís Supper at the very least four times a year, it is to be feared that he despises the Sacrament and is not Christian" - so what they heard was that this was something they needed to do to prove they were Christian - and thus the Lord's Supper became something they do for God - which is often the reason why many think they need to go to church - its something that proves they are Christian - its something they do for God, so that God owes them something.
How anyone could come to this understanding is not hard to understand - for we would all like to imagine that we were perfect, and if not perfect at least better than most, for we also like to imagine that one gets to heaven by living a good life. We all have a measure of pride in us that rebels at acknowledging that we are poor miserable sinners, spiritually blind, dead and enemies of God, who deserve nothing but God's wrath and eternal punishment. We hate to admit that we sin much daily, and would rather think about all the good things we do for God. Call it pride, or call it self idolatry - it is still sin, and not only does sin earn the wrath of God, but it also separates us from God. We need something to take away our sin, something that can wash us clean - we know this every time we look at ourselves in the light of the 10 commandments, for when we so examine ourselves we see our sin, and we see our need for a Savior.
That is why we go to church, not to do something for God, but because when we gather, God does something for us, and we hear the good news that God has sent his Son to be our Savior and take away all our sins. Sometimes it is hard to hear about Jesus dying for our sins, it can make us feel guilty, because we really don't like to think that Jesus died for our sins - we didn't think our sins were that bad, that it should cost so much - sure we knew the passage that says - the wages of sin is death - but we really didn't think it meant it. And if this moves us to repent, that God should love us so much that Jesus should die for us while we were enemies of God - the good thing is that Jesus did die, and his blood washes away all our sins, and all our guilt and makes us a new creation, and enables us to live as children of God - not just live now, but to live eternally.
Sometimes its good to think about things. For example - how often do you eat? Do you need to think about whether or not you will eat this week? No! We know we need to eat daily, even several times a day, and we feel the hunger if we don't - we know that people can die from failing to eat. So if someone were to offer you the bread of life, would you only eat it once? Of course not! Just as we need physical food for our bodies, we need spiritual food for our souls, otherwise our souls would perish - from starvation - not to mention that they would also perish from the penalty of unforgiven sin. God offers us in this bread of heaven, forgiveness of sins, and food which feeds our souls, and the good news of his great love, and of how he sent his son to save us.