Chapter 18 — Part II: The Sacraments — The Holy Eucharist
Section 138. We should, in the next place, carefully examine whether our consciences be defiled by mortal sin, which has to be repented of, in order that it may be blotted out before Communion by the remedy of contrition and confession. The Council of Trent has defined that no one conscious of mortal sin and having an opportunity of going to confession, however contrite he may deem himself, is to approach the Holy Eucharist until he has been purified by sacramental confession.