None of us needs to fall short because we misunderstand and thus neglect the importance of what Jesus did in our behalf.
The Contemporary English Version (CEV) renders this verse, "If you fail to understand that you are the body of the Lord, you will condemn yourselves by the way you eat and drink." The Amplified Bible translates it, "For anyone who eats and drinks without discriminating and recognizing with due appreciation that [it is Christ's] body, eats and drinks a sentence (a verdict of judgment) upon himself."
These translations show two possible understandings of what Paul meant. The CEV contemplates our overall response in how we, knowing we are Christ's body, conduct our daily lives, whereas The Amplified Bible focuses on appreciation of Christ's literal sacrifice while actually taking the bread and wine. Both approaches are correct. In either case, Passover must affect our life in a positive way, or it brings judgment against us.
Along with appreciation and respect, God desires an understanding so deep, strong, and consistent that it motivates us to glorify Him by conforming to His will in daily life. This sense of obligation is not a maudlin sentimentality, but is of such sincere and intense gratitude that it gives us insight into the standard of selflessness Christ exemplified. We must strive to put it into practice in our lives if we are to be like Him and be in our Father's Kingdom.
Put another way, our obligation is to love Them as They loved us—not a resigned attitude of "Okay, I'll do it because I have to" that issues in low-level, letter-of-the-law obedience, but a love that expresses itself in fervent, sacrificial affection, as the woman in Luke 7:36-50 exemplified. This level of love is reasonable to pursue because it drives us far beyond mere superficial conformity. Notice how Romans 12:1-2 draws our attention to this:
I beseech you therefore, brethren, by the mercies of God, that you present your bodies a living sacrifice, holy, acceptable to God which is your reasonable service. And do not be conformed to this world, but be transformed by the renewing of your mind, that you may prove what is that good and acceptable and perfect will of God.
Paul proclaims that this sacrificial love will serve to transform us and provide the proof we need to bolster us in following God's will.