In order for us to commune, we ought to examine ourselves, if we are in a position to commune. This is specifically commanded by the Apostle Paul: “Let a man examine himself, and so let him eat of that bread and drink of that cup. For he who eats and drinks in an unworthy manner eats and drinks judgment to himself not discerning the Lord’s body” (Cor. 11:28-29).
An investigation of ourselves… will show us whether we are able to approach Holy Communion. But be careful! In this self examination we must be neither supersensitive nor senseless. We said elsewhere also that no one is completely worthy to commune, and that Holy Communion is not a reward for the saint, but a strengthening for sinners struggling for holiness.
The self examination and self censure of a spiritual person never has an exonerating result. The faithful Christian always declares himself guilty. But one declaration of guilt varies from another declaration of guilt. If from this self examination one catches himself guilty of grave sins, such as sins of the flesh, explosions of anger, a serious dispute with another person, etc., then he should consider that he cannot commune without confession. If, however, he catches himself guilty of “easily forgivable” sins, which even the greatest saint - bearing flesh and dwelling in the world - commits, then he may decide, with a feeling of this sinfulness of course, to commune . .