The most important effect of the canon law was on marriage, which was now a sacrament and had its sanction not in the laws of men, but in the express decrees of God. Hence even engagements acquired a sacred character unknown to the Roman law; and when a betrothal had once been entered into, it could be broken only in case one or both of the contracting parties desired to enter a monastery.[374] Free consent of both man and woman was necessary for matrimony.[375] There must also be a dowry and a public ceremony.[376] The legitimate wife is thus defined[377]: "A chaste virgin, betrothed in chastity, dowered according to law, given to her betrothed by her parents, and received from the hands of the bridesmaids (_a paranimphis accipienda_); she is to be taken according to the laws and the Gospel and the marriage ceremony must be public; all the days of her life--unless by consent for brief periods to devote to worship--she is never to be separated from her husband; for the cause of adultery she is to be dismissed, but while she lives her husband may marry no other." The blessing of the priest was necessary. About every form connected with the marriage service the Church threw its halo of mystery and symbol to emphasise the sacred character of the union. Thus[378]: "Women are veiled during the marriage ceremony for this reason, that they may know they are lowly and in subjection to their husbands.... A ring is given by the bridegroom to his betrothed either as a sign of mutual love or rather that their hearts may be bound together by this pledge. For this reason, too, the ring is worn on the fourth finger, because there is a certain vein in that finger which they say reaches to the heart." [Sidenote: Clandestine marriages.] Clandestine marriages were forbidden,[379] but the Church always presumed everything it could in favour of marriage and its indissolubility. Thus, Gratian remarks[380]: "Clandestine marriages are, to be sure, contrary to law; nevertheless, they can not be dissolved." The reason for forbidding them was perfectly reasonable: one party might change his or her mind and there would be no positive proof that a marriage had taken place, so that a grave injury might be inflicted on an innocent partner by an unscrupulous one who desired to dissolve the union.[381] Yet the marriage by consent alone without any of the ceremonies or the blessing of the priest was perfectly valid, though not "according to law" (_legitimum_), and could not be dissolved.[382] Not until the great Council of Trent in 1563 was this changed. At that time all marriages were declared invalid unless they had been contracted in the presence of a priest and two or three witnesses.[383] [Sidenote: Protection to women.]