John 6:53-55 says, “Then Jesus said to them, ‘Most assuredly, I say to you, unless you eat the flesh of the Son of Man and drink His blood, you have no life in you.  Whoever eats My flesh and drinks My blood has eternal life, and I will raise him up at the last day.  For My flesh is food indeed, and My blood is drink indeed.'”
Let us then delve into what the flesh and blood of the Son of Man are, and why we have eternal life when we eat and drink the flesh and blood of the Son of Man.
1. What is the Flesh of Son of Man and How Do We Eat It?
John 1:1 says, “In the beginning was the Word, and the Word was with God, and the Word was God.” The God who existed from the beginning came to this earth in human body, and He is Jesus (John 1:14).
Therefore, the flesh of Jesus symbolizes the Word of truth of God, and eating the flesh of the Son of Man is to learn the Word of God written in the 66 books of the Bible.
As Matthew 13:34 says ‘without a parable Jesus did not speak to them,’ there are many parables in the Bible through which we can understand the spiritual realm. Exodus 12:5 onward compares Jesus as Lamb. It says, “Your lamb shall be without blemish, a male of the first year. You may take it from the sheep or from the goats. Your lamb shall be without blemish, a male of the first year. You may take it from the sheep or from the goats. Now you shall keep it until the fourteenth day of the same month. Then the whole assembly of the congregation of Israel shall kill it at twilight. And they shall take some of the blood and put it on the two doorposts and on the lintel of the houses where they eat it.
Generally, we call believers sheep, so some misunderstand that lamb refers to new-believers. But if we contemplate the Bible, we can easily see that lamb refers to Jesus (John 1:29, 1 Peter 1:19, Revelation 5:6, 5:12).
Also, Exodus 12:9-10 mentions in detail on how to eat a lamb, “Do not eat it raw, nor boiled at all with water, but roasted in fire–its head with its legs and its entrails.  You shall let none of it remain until morning, and what remains of it until morning you shall burn with fire.”
Now, let us understand in spiritual way how to eat the lamb, which is the flesh of the Son of Man.
2. How Do We Intake the Word?
First, we must not eat it raw.
Eating it raw means that we understand the Word of God literally. Because God’s Word is written in the inspiration of the Holy Spirit, we must interpret and learn it with the inspiration of the Holy Spirit. If we just read it literally, it is not easy to understand God’s heart and we tend to misunderstand the Word.
For example, Matthew 6:6 says, “But you, when you pray, go into your room, and when you have shut your door, pray to your Father who is in the secret place.” If we eat it raw, namely if we interpret this literally, we have to go into our room whenever we pray. But in the Bible, there is no record that the forefathers of faith prayed in secret rooms. Jesus prayed on hills or mountain (Luke 6:12, Mark 1:35), Daniel opened the window and prayed facing Jerusalem (Daniel 6:10), and Peter prayed on the roof (Acts 10:9).
What, then, does Jesus mean by saying we have to go to our room and pray? Room in the Bible symbolizes people’s heart. When we pray, just as we pass the living room to go into our room, we have to pass our thoughts and go into inner heart to pray to God with all our mind. If we go into the inner room, we are isolated from the outside. In the same way, when we pray, we must cut off idle thoughts and other worldly worries so that we will not use vain repetitions but pray with our whole heart. Likewise, we should not interpret the Bible literally but understand the true meaning and keep it in mind.
Second, we must not boil it in water.
Not boiling the lamb in water means we must not mix anything in the Word of God but eat it as it is. Therefore, when we preach the Word of God, it is not right to mix the words of other famous people, philosophers, and writers, or things about the politics and the society. It is, however, not wrong to give examples with something from the world in order to let the people understand the Word of God easily.
Words of men change as the time goes. Only the Word of God is never changing eternally, and it is the perfect truth that leads us to the way of eternal life. Therefore, we should not learn it mixing it with worldly theories or knowledge.
Third, we must roast it over the fire.
Roasting it over the fire –its head with its legs and its entrails symbolizes that we have to roast and eat the lamb as a whole. Therefore, we should eat all the words written in the 66 books of the Bible and keep it spiritually. We should not read only the parts that we think are necessary but everything from Genesis to Revelation roasted over the fire.
Here, fire means the fire of the Holy Spirit. Because God’s Word is written in the inspiration of the Holy Spirit, we must read it with the fullness and inspiration of the Holy Spirit. Otherwise, we can only learn it as knowledge, and we will not be able to grow up spiritually. But if we learn the Word of God with inspiration of the Holy Spirit, we will feel that it is sweeter than honeycomb. This is to roast it over the fire. Only in this way will we understand God’s Word and digest it so that it will become our spiritual food. Then, we will change into spiritual persons.
Fourth, we must not let any of it remain until morning, and what remains of it until morning we have to burn with fire.
God said, “You must kill the lamb at the sunset, eat the whole lamb roasted over the fire at that night, and you must not let any of it remain until morning.”
Today’s world is a dark world where the enemy devil and Satan have the authority to rule, and it can be expressed as night. When the time comes, the Lord, who is the true light, will come and the darkness will go away. Everything will be recovered, and it will become morning, which is the world of light.
Therefore, we must learn the Word of God before the Lord comes back so that we will be able to prepare ourselves as the brides of the Lord. Also, because this life is 70 or 80 years at most, and we do not know when we will go to the Lord, we should learn the Word of God more diligently until we meet the Lord and try to become spiritual persons.
3. What is the Blood of Son of Man and How do We Drink it?
— The Importance of Practicing the Word
For us to live, we must eat food and drink water. If we do not take any water, the food will not be digested, and we cannot but die. When the food enters the stomach along with water, it is digested. The nutrients are absorbed and the wasted will be evacuated. In the same way, when we eat the flesh of the Son of Man, if we do not drink His blood, we cannot digest and thus we cannot have eternal life.
What, then, does ‘drinking the blood’ mean?
It is to put into practice the Word of God with faith. After we listen to the Word of god, it is very important to put it into practice, and this is faith. If we do not act the Word after listening to it, it is of no use.
Just as the food we eat gets digested, the nutrients are absorbed, and the waste is evacuated, spiritually, if we hear the Word of God and practice it, God’s Word, which is the truth, will be absorbed and the untruths, which are opposite, will be evacuated, so that our dark heart will change into white heart.
For example, to get rid of the sin of hatred, we should first listen to Word of truth that says, ‘love’, keep it in our mind, and practice it. Then, the word of truth will be digested and the nutrient called ‘love’ will be absorbed in us, and the waste called ‘hatred’ will be excreted. As we get rid of dirty heart in this way, we will have white and beautiful heart, namely the heart of truth.
The first man Adam whom God created was made in God’s image and lived in the Garden of Eden without any shortage, eating all the fruits except the fruit of the knowledge. God walked with Adam and taught him only goodness and truth.
But when Adam was tempted by Satan, he disobeyed God’s Word and ate from the tree of the knowledge of good and evil. Sin and evil came into men. Also, as God said, “You will surely die,” Adam’s spirit died and the communication with God who is spirit was cut off. Instead, men became friends with the enemy devil and Satan.
As time went, more untruths came into men, and sins and evil are prevailing in the world now. Men became no different than animals in the sight of God, and today, there are some people who are even worse than animals.
In order to solve this problem of sin, Jesus came to this earth, and whoever accepts Jesus as the Savior will receive the Holy Spirit in their heart as a gift from God. The heart of men have both good and evil heart, and the Holy Spirit moves the good heart for us to hear and understand God’s Word. He helps us to throw away evil hearts continuously.
But it does not mean that the Holy Spirit helps us even though we just sit and stay. For example, to make a machine work, we must put fuel. In the same way, we have to pray to be filled with the Holy Spirit and receive grace and strength from above. By doing this, we can eat God’s Word properly. Namely, when we eat the flesh and drink the blood of the Son of Man with praying, God’s Word will become our blood and flesh spiritually so that we will have eternal life. As we do this, the untruths and impurities will be evacuated, so that our dark heart will be changed into white heart.
That is why Romans 10:10 says, “For with the heart one believes unto righteousness, and with the mouth confession is made unto salvation.” If we truly believe in our heart, we will plant God’s Word in our heart, so that the untruths that are against the Word will be removed and the truth will come in us. Then, our heart will become righteous and clean. It is to throw away former conduct and become a new person. Likewise, believers change into righteous man, not sinful man, and finally reach salvation with faith.