9. What are appropriate signs of reverence with respect to the Body and Blood of Christ?
The Body and Blood of Christ present under the appearances of bread and wine are treated with the greatest reverence both during and after the celebration of the Eucharist (cf. Mysterium Fidei, nos. 56-61). For example, the tabernacle in which the consecrated bread is reserved is placed "in some part of the church or oratory which is distinguished, conspicuous, beautifully decorated, and suitable for prayer" (Code of Canon Law, Can. 938, §2). According to the tradition of the Latin Church, one should genuflect in the presence of the tabernacle containing the reserved sacrament. In the Eastern Catholic Churches, the traditional practice is to make the sign of the cross and to bow profoundly. The liturgical gestures from both traditions reflect reverence, respect, and adoration. It is appropriate for the members of the assembly to greet each other in the gathering space of the church (that is, the vestibule or narthex), but it is not appropriate to speak in loud or boisterous tones in the body of the church (that is, the nave) because of the presence of Christ in the tabernacle. Also, the Church requires everyone to fast before receiving the Body and Blood of Christ as a sign of reverence and recollection (unless illness prevents one from doing so). In the Latin Church, one must generally fast for at least one hour; members of Eastern Catholic Churches must follow the practice established by their own Church.
10. If someone without faith eats and drinks the consecrated bread and wine, does he or she still receive the Body and Blood of Christ?
If "to receive" means "to consume," the answer is yes, for what the person consumes is the Body and Blood of Christ. If "to receive" means "to accept the Body and Blood of Christ knowingly and willingly as what they are, so as to obtain the spiritual benefit," then the answer is no. A lack of faith on the part of the person eating and drinking the Body and Blood of Christ cannot change what these are, but it does prevent the person from obtaining the spiritual benefit, which is communion with Christ. Such reception of Christ's Body and Blood would be in vain and, if done knowingly, would be sacrilegious (1 Cor 11:29). Reception of the Blessed Sacrament is not an automatic remedy. If we do not desire communion with Christ, God does not force this upon us. Rather, we must by faith accept God's offer of communion in Christ and in the Holy Spirit, and cooperate with God's grace in order to have our hearts and minds transformed and our faith and love of God increased.
11. If a believer who is conscious of having committed a mortal sin eats and drinks the consecrated bread and wine, does he or she still receive the Body and Blood of Christ?
Yes. The attitude or disposition of the recipient cannot change what the consecrated bread and wine are. The question here is thus not primarily about the nature of the Real Presence, but about how sin affects the relationship between an individual and the Lord. Before one steps forward to receive the Body and Blood of Christ in Holy Communion, one needs to be in a right relationship with the Lord and his Mystical Body, the Church - that is, in a state of grace, free of all mortal sin. While sin damages, and can even destroy, that relationship, the sacrament of Penance can restore it. St. Paul tells us that "whoever eats the bread or drinks the cup of the Lord unworthily will have to answer for the body and blood of the Lord. A person should examine himself, and so eat the bread and drink the cup" (1 Cor 11:27-28). Anyone who is conscious of having committed a mortal sin should be reconciled through the sacrament of Penance before receiving the Body and Blood of Christ, unless a grave reason exists for doing so and there is no opportunity for confession. In this case, the person is to be mindful of the obligation to make an act of perfect contrition, that is, an act of sorrow for sins that "arises from a love by which God is loved above all else" (Catechism, no. 1452). The act of perfect contrition must be accompanied by the firm intention of making a sacramental confession as soon as possible.
12. Does one receive the whole Christ if one receives Holy Communion under a single form?
Yes. Christ Jesus, our Lord and Savior, is wholly present under the appearance either of bread or of wine in the Eucharist. Furthermore, Christ is wholly present in any fragment of the consecrated Host or in any drop of the Precious Blood. Nevertheless, it is especially fitting to receive Christ in both forms during the celebration of the Eucharist. This allows the Eucharist to appear more perfectly as a banquet, a banquet that is a foretaste of the banquet that will be celebrated with Christ at the end of time when the Kingdom of God is established in its fullness (cf. Eucharisticum Mysterium, no. 32).
Fr. Antonius David Tristianto, O.Carm.