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In 1 Corinthians 11:17–34, a passage dedicated to discussing communion or the Lord’s Supper, the apostle Paul gives some important instructions: “Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty concerning the body and blood of the Lord. Let a person examine himself, then, and so eat of the bread and drink of the cup. For anyone who eats and drinks without discerning the body eats and drinks judgment on himself. That is why many of you are weak and ill, and some have died. But if we judged ourselves truly, we would not be judged. But when we are judged by the Lord, we are disciplined so that we may not be condemned along with the world” (1 Corinthians 11:27–32, ESV).
This passage gives a strong warning against drinking the cup of the Lord in an unworthy manner (1 Corinthians 11:27). Doing so brings judgment (11:29), which can include weakness, illness, and even death (11:30). The preventative measure Paul recommends is to examine yourself (11:28) and to judge yourself (11:31). In light of these verses, some, after examining themselves, choose to not take communion. Instead, they decide to wait until they have had the opportunity to fully repent and confess their sins to the Lord (1 John 1:9) and/or make restitution with a person they have sinned against.
Some see Matthew 5:23–24 as outlining a principle that could apply to taking communion: “Therefore, if you are offering your gift at the altar and there remember that your brother or sister has something against you, leave your gift there in front of the altar. First go and be reconciled to them; then come and offer your gift.” We take communion in remembrance of Christ (Luke 22:19). What are we remembering? His death and shed blood, which paid the penalty for our sins. Part of remembering Christ’s sacrifice is making sure our sins are biblically dealt with as we remember what He did for us.
When should you not take communion? There is no biblical command “Do not take communion in these situations.” So, it is a matter of conscience and conviction from the Lord. Ask God for wisdom (James 1:5). Examine yourself (1 Corinthians 11:28). Ask the Lord to reveal to you if there is any wicked way in you (Psalm 139:24). Confess your sins to God (1 John 1:9). If you feel convicted that something is not right with your relationship with God and/or others, it is allowable, maybe even advisable, to not take communion until things are made right.
It is also important to not view perfection as the requirement for taking communion. If perfection were the standard, no one could ever take communion. Being ready to take communion is not a matter of sinlessness or having perfectly dealt with the ramifications of every sin you have committed. Rather, strive to be, as much as it depends on you, fully reconciled with the people who are in your life (Romans 12:18).