I answer that, Just as by carnal procreation man receives natural being, so by the sacraments he receives the spiritual being of grace. Wherefore just as the tie that is contracted by carnal procreation is natural to man, inasmuch as he is a natural being, so the tie that is contracted from the reception of the sacraments is after a fashion natural to man, inasmuch as he is a member of the Church. Therefore as carnal relationship hinders marriage, even so does spiritual relationship by command of the Church. We must however draw a distinction in reference to spiritual relationship, since either it precedes or follows marriage. If it precedes, it hinders the contracting of marriage and voids the contract. If it follows, it does not dissolve the marriage bond: but we must draw a further distinction in reference to the marriage act. For either the spiritual relationship is contracted in a case of necessity, as when a father baptizes his child who is at the point of death---and then it is not an obstacle to the marriage act on either side---or it is contracted without any necessity and through ignorance, in which case if the person whose action has occasioned the relationship acted with due caution, it is the same with him as in the former case---or it is contracted purposely and without any necessity, and then the person whose action has occasioned the relationship, loses the right to ask for the debt; but is bound to pay if asked, because the fault of the one party should not be prejudicial to the other.