But what if I understand how Catholics believe, but I can't believe it myself?
No one here believed in the Eucharistic Lord through anything but revelation. It is a grace of God, plain and simple. You could try of yourself to figure it out all your life and never have it happen, unless you abandoned yourself to God,
patiently allowing Him to reveal it to you.
Second, Jesus was speaking only to a specific group of Jews, not to everyone in an all encompassing statement.
John 6:52-54:
The Jews then disputed among themselves, saying, "How can this man give us his flesh to eat?" So Jesus said to them, "Truly, truly, I say to you, unless you eat the flesh of the Son of man and drink his blood, you have no life in you; he who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day.
The Jews would have no life in them because of their rejection of Jesus' revelation to them. They turned their back on His teaching, so for them, their refusal to partake of Communion could very well have been damning.
Take this passage for example. In Mark 10:17 Jesus is asked, " 'Good Teacher, what must I do to inherit eternal life?' " To which Jesus replied in part, "...go, sell what you have, and give to the poor, and you will have treasure in heaven; and come, follow me." Here we have Jesus telling a young man who has followed the Ten Commandments since his youth that he will not have eternal life unless he gives away his possessions. Does that mean that I am bound for Hell because I still have possessions? In my case, as of right now, no. But if at some later date I was called by Christ to do such a thing and did not, it could very well mean I will not see Heaven. Jesus telling the Jews they must eat of His flesh and drink of His Blood is a similar demand. It is their outright defiance, their selfishness and pride that would have ****** them, not whether or not they had taken Communion, specifically.
Saint Paul says as much in 1 Corinthians 11:27 when he says, "Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord." Do these contradict Jesus' statements that
whoever eats of His table will have eternal life? No, because Jesus was concerned with interior conversion and growth in holiness. Drinking of the Cup can be the greatest blessing or the worst curse, depending upon your disposition. In one case you are accepting Christ in a most intimate and profound way, in another you are profaning the very blood that sanctified you. In the second case, partaking of the Body and Blood of Christ would have the opposite effect of what Christ promised.
Am I making sense?
Neal