Article — Slater, Manual of Moral Theology
Article XIII. Violence and Fear
Violence is the onset of force too great to be resisted, and fear is a perturbation of mind arising from present or future danger. Here we treat of fear caused by extrinsic violence, inasmuch as it is a diriment impediment of marriage.
When marriage is contracted through grave fear, caused unjustly by a free agent with a view to extorting marriage, ecclesiastical law makes it null and void. Whether such a marriage is invalid by natural law is a moot point among Doctors. Fear may, indeed, sometimes be so excessive that it takes away the use of reason, so that a man under its influence does not know what he is doing. If a man married under the influence of such terror, the marriage would of course be invalid for want of consent. But commonly even grave fear does not produce such effects; a man in danger of shipwreck or death knows as a rule what he is doing, and if he marries in such circumstances, though induced by fear to do so, the marriage will be valid. But when he is unjustly forced by someone to marry against his will, the injury done to him is a sufficient reason for the Church to make the marriage null and void, even though he knew what he was doing and consented to the marriage. The only difference between this case and the former lies in the injury inflicted by the fear caused by a free agent. This however, does not seem sufficient ground for asserting the nullity of the contract by natural law, though it affords a just reason why positive law should make it invalid. The better opinion, then, seems to be that grave fear is a diriment impediment of marriage by ecclesiastical law when the fear is caused unjustly by someone with a view to compelling the party to marry against his will. Hence, if one who had violated a woman was threatened with a beating and married her in order to escape it, the marriage would be valid. Fear arising from reverence for parents and superiors is in general not sufficiently serious to make marriage contracted under its influence null and void. In certain circumstances, however, such a fear may become grave and sufficient to annul marriage. Much depends on the character of the party who was influenced by fear and on the means employed to compel acquiescence to the wishes of harsh and severe parents or guardians. The question as to whether in any particular case there was grave fear is a question of fact to be determined by the ecclesiastical judge after weighing all the circumstances of the case (Can. 1087).
p. ii, 229
Although marriage has beer contracted under the influence of grave fear sufficient to render it invalid, the marriage may afterward become valid if fear disappears, and the party who was under its influence freely cohabits with the other and expresses matrimonial consent. In this case it will not be necessary to repeat the external solemnization of the marriage unless the impediment was publicly known. It will be sufficient if the parties manifest their consent to be man and wile privately when freed from the influence of grave fear.
As may be gathered from what has already been said, slight fear, such as any ordinarily constituted person can despise, does not invalidate marriage, even when it is caused unjustly with a view to extort marriage.
p. ii, 230–231