Whether to approach this sacrament with consciousness of sin is the gravest of all sins?

Objections

Objection 1 : It seems that to approach this sacrament with consciousness of sin is the gravest of all sins; because the Apostle says (1 Cor. 11:27): "Whosoever shall eat this bread, or drink the chalice of the Lord unworthily, shall be guilty of the body and of the blood of the Lord": upon which the gloss observes: "He shall be punished as though he slew Christ." But the sin of them who slew Christ seems to have been most grave. Therefore this sin, whereby a man approaches Christ's table with consciousness of sin, appears to be the gravest.
Objection 2 : Further, Jerome says in an Epistle (xlix): "What hast thou to do with women, thou that speakest familiarly with God at the altar?" [*The remaining part of the quotation is not from St. Jerome]. Say, priest, say, cleric, how dost thou kiss the Son of God with the same lips wherewith thou hast kissed the daughter of a harlot? "Judas, thou betrayest the Son of Man with a kiss!" And thus it appears that the fornicator approaching Christ's table sins as Judas did, whose sin was most grave. But there are many other sins which are graver than fornication, especially the sin of unbelief. Therefore the sin of every sinner approaching Christ's table is the gravest of all.
Objection 3 : Further, spiritual uncleanness is more abominable to God than corporeal. But if anyone was to cast Christ's body into mud or a cess-pool, his sin would be reputed a most grave one. Therefore, he sins more deeply by receiving it with sin, which is spiritual uncleanness, upon his soul.