Objection 1. It does not appear to be lawful to receive this sacrament daily, because, as Baptism shows forth our Lord's Passion, so also does this sacrament. Now one may not be baptized several times, but only once, because "Christ died once" only "for our sins," according to 1 Peter 3:18. Therefore, it seems unlawful to receive this sacrament daily.
Objection 2. Further, the reality ought to answer to the figure. But the Paschal Lamb, which was the chief figure of this sacrament, as was said above (Question 73, Article 9) was eaten only once in the year; while the Church once a year commemorates Christ's Passion, of which this sacrament is the memorial. It seems, then, that it is lawful to receive this sacrament not daily, but only once in the year.
Objection 3. Further, the greatest reverence is due to this sacrament as containing Christ. But it is a token of reverence to refrain from receiving this sacrament; hence the Centurion is praised for saying (Matthew 8:8), "Lord, I am not worthy that Thou shouldst enter under my roof"; also Peter, for saying (Luke 5:8), "Depart from me, for I am a sinful man, O Lord." Therefore, it is not praiseworthy for a man to receive this sacrament daily.
Objection 4. Further, if it were a praiseworthy custom to receive this sacrament frequently, then the oftener it were taken the more praise-worthy it would be. But there would be greater frequency if one were to receive it several. times daily; and yet this is not the custom of the Church. Consequently, it does not seem praiseworthy to receive it daily.
Objection 5. Further, the Church by her statutes intends to promote the welfare of the faithful. But the Church's statute only requires Communion once a year; hence it is enacted (Extra, De Poenit. et Remiss. xii): "Let every person of either sex devoutly receive the sacrament of the Eucharist at least at Easter; unless by the advice of his parish priest, and for some reasonable cause, he considers he ought to refrain from receiving for a time." Consequently, it is not praiseworthy to receive this sacrament daily.
On the contrary, Augustine says (De Verb. Dom., Serm. xxviii): "This is our daily bread; take it daily, that it may profit thee daily."
I answer that, There are two things to be considered regarding the use of this sacrament. The first is on the part of the sacrament itself, the virtue of which gives health to men; and consequently it is profitable to receive it daily so as to receive its fruits daily. Hence Ambrose says (De Sacram. iv): "If, whenever Christ's blood is shed, it is shed for the forgiveness of sins, I who sin often, should receive it often: I need a frequent remedy." The second thing to be considered is on the part of the recipient, who is required to approach this sacrament with great reverence and devotion. Consequently, if anyone finds that he has these dispositions every day, he will do well to receive it daily. Hence, Augustine after saying, "Receive daily, that it may profit thee daily," adds: "So live, as to deserve to receive it daily." But because many persons are lacking in this devotion, on account of the many drawbacks both spiritual and corporal from which they suffer, it is not expedient for all to approach this sacrament every day; but they should do so as often as they find themselves properly disposed. Hence it is said in De Eccles. Dogmat. liii: "I neither praise nor blame daily reception of the Eucharist."
Reply to Objection 1. In the sacrament of Baptism a man is conformed to Christ's death, by receiving His character within him. And therefore, as Christ died but once, so a man ought to be baptized but once. But a man does not receive Christ's character in this sacrament; He receives Christ Himself, Whose virtue endures for ever. Hence it is written (Hebrews 10:14): "By one oblation He hath perfected for ever them that are sanctified." Consequently, since man has daily need of Christ's health-giving virtue, he may commendably receive this sacrament every day.
And since Baptism is above all a spiritual regeneration, therefore, as a man is born naturally but once, so ought he by Baptism to be reborn spiritually but once, as Augustine says (Tract. xi in Joan.), commenting on John 3:4, "How can a man be born again, when he is grown old?" But this sacrament is spiritual food; hence, just as bodily food is taken every day, so is it a good thing to receive this sacrament every day. Hence it is that our Lord (Luke 11:3), teaches us to pray, "Give us this day our daily bread": in explaining which words Augustine observes (De Verb. Dom., Serm. xxviii): "If you receive it," i.e. this sacrament, every day, "every day is today for thee, and Christ rises again every day in thee, for when Christ riseth it is today."
Reply to Objection 2. The Paschal Lamb was the figure of this sacrament chiefly as to Christ's Passion represented therein; and therefore it was partaken of once a year only, since Christ died but once. And on this account the Church celebrates once a year the remembrance of Christ's Passion. But in this sacrament the memorial of His Passion is given by way of food which is partaken of daily; and therefore in this respect it is represented by the manna which was given daily to the people in the desert.
Reply to Objection 3. Reverence for this sacrament consists in fear associated with love; consequently reverential fear of God is called filial fear, as was said in I-II, 67, 4, ad 2; II-II, 19, 9,11,12; because the desire of receiving arises from love, while the humility of reverence springs from fear. Consequently, each of these belongs to the reverence due to this sacrament; both as to receiving it daily, and as to refraining from it sometimes. Hence Augustine says (Ep. liv): "If one says that the Eucharist should not be received daily, while another maintains the contrary, let each one do as according to his devotion he thinketh right; for Zaccheus and the Centurion did not contradict one another while the one received the Lord with joy, whereas the other said: 'Lord I am not worthy that Thou shouldst enter under my roof'; since both honored our Saviour, though not in the same way." But love and hope, whereunto the Scriptures constantly urge us, are preferable to fear. Hence, too, when Peter had said, "Depart from me, for I am a sinful man, O Lord," Jesus answered: "Fear not."
Reply to Objection 4. Because our Lord said (Luke 11:3), "Give us this day our daily bread," we are not on that account to communicate several times daily, for, by one daily communion the unity of Christ's Passion is set forth.
Reply to Objection 5. Various statutes have emanated according to the various ages of the Church. In the primitive Church, when the devotion of the Christian faith was more flourishing, it was enacted that the faithful should communicate daily: hence Pope Anaclete says (Ep. i): "When the consecration is finished, let all communicate who do not wish to cut themselves off from the Church; for so the apostles have ordained, and the holy Roman Church holds." Later on, when the fervor of faith relaxed, Pope Fabian (Third Council of Tours, Canon 1) gave permission "that all should communicate, if not more frequently, at least three times in the year, namely, at Easter, Pentecost, and Christmas." Pope Soter likewise (Second Council of Chalon, Canon xlvii) declares that Communion should be received "on Holy Thursday," as is set forth in the Decretals (De Consecratione, dist. 2). Later on, when "iniquity abounded and charity grew cold" (Matthew 24:12), Pope Innocent III commanded that the faithful should communicate "at least once a year," namely, "at Easter." However, in De Eccles. Dogmat. xxiii, the faithful are counseled "to communicate on all Sundays."
Source: Summa Theologica (New Advent)