"A sacrament is so termed because it contains something sacred. Now a thing can be styled sacred from two causes; either absolutely, or in relation to something else. The difference between the Eucharist and other sacraments having sensible matter is that whereas the Eucharist contains something which is sacred absolutely, namely, Christ's own body; the [...]
"Perfection is twofold. The first lies within man himself; and he attains it by growth: such perfection belongs to Confirmation. The other is the perfection which comes to man from the addition of food, or clothing, or something of the kind; and such is the perfection befitting the Eucharist, which is the spiritual refreshment." -St. [...]
"Absolutely speaking, the sacrament of the Eucharist is the greatest of all the sacraments… because it contains Christ Himself substantially: whereas the other sacraments contain a certain instrumental power which is a share of Christ's power." -St. Thomas Aquinas
"A thing is one in perfection, when it is complete through the presence of all that is needed for its end; as a man is complete by having all the members required for the operation of his soul, and a house by having all the parts needful for dwelling therein. And so this sacrament is [...]
"The Apostle says (1 Cor. 10:17): "For we, being many, are one bread, one body, all that partake of one bread": from which it is clear that the Eucharist is the sacrament of the Church's unity." Source: ÿSt. Thomas Aquinas,ÿSumma Theologica
"A sacrament is so termed because it contains something sacred. Now a thing can be styled sacred from two causes; either absolutely, or in relation to something else. The difference between the Eucharist and other sacraments having sensible matter is that whereas the Eucharist contains something which is sacred absolutely, namely, Christ's own body; the [...]
"Perfection is twofold. The first lies within man himself; and he attains it by growth: such perfection belongs to Confirmation. The other is the perfection which comes to man from the addition of food, or clothing, or something of the kind; and such is the perfection befitting the Eucharist, which is the spiritual refreshment." [...]
Absolutely speaking, the sacrament of the Eucharist is the greatest of all the sacraments... because it contains Christ Himself substantially. Source: ÿSt. Thomas Aquinas, Summa Theologica
"The breaking of the host denotes three things: first, the rending of Christ's body, which took place in the Passion; secondly, the distinction of His mystical body according to its various states; and thirdly, the distribution of the graces which flow from Christ's Passion, as Dionysius observes (Eccl. Hier. iii). Hence this breaking does not [...]
"The Church's sacraments are ordained for helping man in the spiritual life. But the spiritual life is analogous to the corporeal, since corporeal things bear a resemblance to spiritual. Now it is clear that just as generation is required for corporeal life, since thereby man receives life; and growth, whereby man is brought to maturity: [...]