Reply to Objection 2: Although the second marriage, considered in itself, is a perfect sacrament, yet if we consider it in relation to the first marriage, it is somewhat a defective sacrament, because it has not its full signification, since there is not a union of only one woman with only one man as in the marriage of Christ with the Church. And on account of this defect the blessing is omitted in a second marriage. This, however, refers to the case when it is a second marriage on the part of both man and woman, or on the part of the woman only. For if a virgin marry a man who has had another wife, the marriage is blessed nevertheless. Because the signification is preserved to a certain extent even in relation to the former marriage, since though Christ has but one Church for His spouse, there are many persons espoused to Him in the one Church. But the soul cannot be espoused to another besides Christ, else it commits fornication with the devil. Nor is there a spiritual marriage. For this reason when a woman marries a second time the marriage is not blessed on account of the defect in the sacrament.
Reply to Objection 3: The perfect signification is found in a second marriage considered in itself, not however if it be considered in relation to the previous marriage, and it is thus that it is a defective sacrament.
Reply to Objection 4: A second marriage in so far as there is a defect in the sacrament, but not as a sacrament, is an impediment to the sacrament of Order.