Warren Wiersbe states: ‘No one should take Communion who is not a true believer. Nor should a believer take Communion if their heart is not right with God and with their fellow believers. That’s why churches have a time of spiritual preparation [the confession and making peace with each other] before we take [Communion], so that partakers don’t bring [rebuke and judgment] on themselves.’

So before you drink from the communion cup, just think what was in the cup Jesus drank from in Gethsemane on the night before He was crucified. – You can drink from the cup with sweet assurance because He first drank from the cup in agony. On the eve of His death He prayed: ‘My soul is overwhelmed with sorrow to the point of death… Father, everything is possible for you. Take this cup from me. Yet not what I will, but what you will’ (Mark 14:34-36). Note the words ‘overwhelmed with sorrow.’ (If you think your sin is no big deal, perhaps those words will help to change your mind.) Christ drank from the cup of God’s wrath so that you could drink from the cup of God’s grace.

[Note: Source: The UCB Word For Today , 24/10/2013]

Source: The Transformation Study Bible (NLT), Colorado USA: David C. Cook Publishers (2009), Catalyst Notes: Remembering Our Saviour at Communion, p.1768 by Dr Warren W. Wiersbe