1,427. The Obligation to Marry; Kiddushin

Hilchos Ishus 1:2

Marrying a wife fulfills a Torah obligation. Marriage is effected in three ways: through the exchange of money, through a written document and through intimate relations. Intimate relations and a written document have their basis in the Torah, while the exchange of money is of rabbinic origin. This stage of the marriage process is called eirusin or kiddushin (in English, betrothal). A woman who has undergone this stage of the marriage process is called mekudeshes or me’ureses.

Hilchos Ishus 1:3

Once this stage of marriage has been completed and a woman is mekudeshes, she is considered married even though the marriage has not yet been consummated and she has not yet moved into her husband’s home. If anyone other than her husband were to engage in intimate relations with her, it is adultery, a capital offense. If the husband wants to divorce her, he must give her a get (divorce document).