For Catholics Striving for Holiness:
When our Lord speaks about the Apostles being clean, now, just before the institution of the Blessed Eucharist, he is referring to the need for the soul to be free from sin if it is to receive this Sacrament. St Paul repeats this teaching when he says:
“Whoever eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord” (1 Cor 11:27).
On the basis of these teachings of Jesus and the Apostles, the Church lays down that anyone who is conscious of having committed a grave sin, or who has any positive doubt on that score, must go to Confession before receiving Holy Communion.
If one has not gone to confession first, one must NOT receive Holy Communion if HE OR SHE IS GUILTY of having committed the following MORTAL sins, KNOWING that they are GRAVE and in spite of that, FREELY CHOSE to do it:1. Having MISSED a SUNDAY or HOLY DAY MASS WITHOUT a valid reason (i. e., out of laziness, giving priority to sports, shopping, parties etc.) (Read more.)