Thomas Aquinas

“ 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. ”

“ A second marriage is stated not to be good, not that it is unlawful, but because it lacks the honor of the signification which is in a first marriage, where one husband has one wife, as in the case of Christ and the Church. ”

“ Men who are consecrated to Divine things are debarred not only from unlawful things, but even from things which have any appearance of turpitude; and consequently they are debarred from second marriages, which lack the decorum which was in a first marriage. ”