A relative of mine who is a cradle catholic is going to marry a non-Catholic (Methodist) in a strictly Methodist ceremony without a dispensation so far as I know. My question is, can he still receive the sacraments (specifically the Holy Eucharist) if he knowingly marries outside the Catholic Church?
He will not be able to receive the Eucharist because he will be in the state of mortal sin. The Catholic Church requires that Catholics be married through it. For a Catholic to knowingly and deliberately marry without the Catholic Church's permission is to sin seriously. Because the Church will not consider such a marriage to be valid, he will sin mortally every time he has marital relations with someone to whom he is not validly married. He needs to see his priest. We will be praying for him.
Fr. Vincent Serpa, O.P.