4. Elements of marriage
The essential elements of the marriage are three: the unit, the indissolubility and the fertility. Human beings can freely decide to marry or not, but it is not in their hands change the meaning of marriage.
The first two elements are expressed with a short and graphic phrase: "forever together."
Marriage is the decision of a man and woman who live for each other, helping mutually with all that they are and have. Therefore, the spouses "are no longer two, but one flesh" (Matthew 19, 6).
A man or a woman may only love partially to another person who is not her wife or his husband. True love is absolute and is not shared.
The loyalty and faithfulness to the other is possible for all life, but difficulties can arise especially for those who do not have the supernatural help of the sacrament. The priest says at the wedding: "Christ gives you strength to be faithful to each other and have the responsibilities of marriage together."
(Painting El banquero y su esposa. REYMERSWAELE, Marinus van. Museo de Bellas Artes. Valenciennes)