Jesus told the Jews they must eat His body and drink His blood because He was the bread of life. The Jews and many of His disciples were offended at His revelation. I don’t think the Jews were offended at the idea of eating His flesh and drinking His blood, they were mad at Him for claiming to come from God.
John6:56 He that eats My flesh and drinks My blood, dwells in Me, and I in him.
The Jews didn’t understand what Jesus was telling them, His body He offered them was a spiritual meal. If they would believe He was the Son of God and He came to save them, in essence they would be partaking of His life. How could a man dwell in Him if you ate Him all up? The Jews practiced the Passover meal every year, and they ate a perfect young lamb which represented the Messiah. So when Jesus introduced Himself as the Christ they would not accept Him. They had an image in their mind of who the Messiah would be and the Son of a carpenter did not resemble their image. They wanted a Samson or Gideon, not a wimp who went around telling about God as His Father.
Luke 22:19-20 Jesus took the bread and said this is My body which is broken for you. Then He took the cup and said this cup is the new testament in My blood. Eat this in remembrance of Me.
Jesus was fulfilling the prophesy of Isaiah when he wrote in his book. Isaiah said, with His stripes we are healed and He was bruised for all our sins. The bread represents His body and the cup represents His blood. All He asks us to do is remember Him and what He did for us. The bread and the wine are symbols of His body which is His life. When we take communion we recall what Jesus did for us on the cross. It’s quite easy to forget something that was given to us over two thousand years ago.
2 Corinthians 11:29 He that eats and drinks unworthily, eats and drinks judgement upon himself, not discerning the Lord‘s body.
If we don’t take communion by faith, then we are not protected from the curse of the law. God does not put sickness or disease on people, we do that or we get it from the devil because we don’t resist him! The church at Corinth had cliques and divisions, the participants had no business taking communion. In the Catholic church you could not receive communion unless you went to the priest and confessed your sins. Eating Christ’s body and drinking His blood exempted you from the curse, eating and drinking unworthily opens you to the curse.
2 Corinthians 11:31 If we would judge ourselves, we should not be judged with the world.
The world has no covenant with the Lord, they are under the curse of the law, they are under judgement. Being saved does not always exempt you from judgement, obeying your Lord offers divine protection. Jesus offered Himself for all mankind, He redeemed us from the curse of the law, we must hold His sacrifice in high regard.