Massekhet Ketubot is the central tractate in Seder Nashim. It provides clarification of most of the matters that constitute the relationship between husband and wife: conjugal relations, mutual obligations, and monetary arrangements between them. Due to the broad spectrum of topics covered in it, which branch out into many different areas of halakha, the early commentaries called Massekhet Ketubot the miniature Talmud (Shas katan) or the key to the Talmud (mafte’ah ha-Shas).
Marriage is a relationship of kedusha that can only be broken by the death of either the husband or the wife, or a geṭ. Still, according to the halakha, the relationship between spouses is governed by mutual responsibilities which are agreed upon by the two sides. These agreements are binding based on a contract – the ketuba. The very term, ketuba, indicates the centrality of the written, contractual agreement, and it is called by this name because it is effectively the single written contract that every Jewish person will need in the course of their lives. Since the ketuba contains the agreed upon mutual responsibilities between husband and wife, it logically follows that Massekhet Ketubot is a study and analysis of the rights and obligations of married life.
The importance of the ketuba is not limited to the agreements contained in it. The Sages ruled that a marriage that does not have a ketuba, cannot be considered a marriage at all, since the main difference between a casual sexual relationship outside of marriage (zenut) and marriage is the existence of a documented agreement between the couple that spells out their mutual responsibilities – including obligations should the marital relationship come to an end. Thus, from the perspective of the Sages, marriage without a ketuba is to be considered zenut.
The Torah obligations that a man has to his wife include she’er kesut ve-onah – to feed her, to clothe her and to share with her a sexual relationship – based on the passage in Shemot (21:10). On a Rabbinic level, he is further obligated to pay for her medical treatments and to redeem her from captivity, should the need arise. The wife’s obligations to her husband are all Rabbinic in nature. They include various household duties, as well as contributing to the support of the household.
Another aspect of the ketuba as established by the Sages is to clarify the rights of the wife in the event of her husband’s death or divorce. On its most basic level, the ketuba guarantees a cash payment to the wife should the marriage end. This sum, referred to as ikkar ketuba, is 200 dinar for a betula (virgin) and 100 dinar for an almana (widow). The husband can add to this sum, but cannot pay less than this amount. Furthermore, the Sages rule that all of the husband’s possessions – real estate and liquid assets – are all obligated to pay this debt. Should the husband die, even as his children inherit his estate, the widow has the right to remain in his house and live off of his assets until such time as she remarries.
Since every marriage is based on a series of expectations and agreements, just as with any other agreement there is the possibility of arguments between the two sides. There is always potential for disagreements between husbands and wives – which are not really the concern of the courts unless the couple decides to end their marriage. There are, however, times that the courts are called in to play a role, for example where there is an accusation that one of the parties did not live up to their part of the agreement. Such accusations can relate to a basic issue in the agreed upon marriage, where one side claims that they were fooled and would never have agreed to the marriage had they been in possession of the information in the first place, or to secondary agreements, where the claim is that one side is not living up to their responsibilities as delineated in the ketuba.
When such issues come before the beit din, there are two stages to the halakhic deliberation. First of all, there is a need to clarify the truth of the claim. In marriage – more than in any other area of agreement between two parties – there are issues that are difficult or impossible to fully clarify. For example, when the husband claims that he found that his wife was not a virgin, it is likely that neither his claim nor his wife’s arguments in her defense will have objective or unbiased support. The court may therefore be forced to rely on general principles regarding the credibility of individual claimants. The second stage will be the court’s ability to find methods to rectify the matter at hand. On occasion the beit din will annul marriages, force the husband to divorce his wife, while paying the ketuba, force the husband to divorce his wife without paying the ketuba, or find other methods of sanctions to ensure that both parties live up to their obligations.
These topics, ranging from family law to finances, are the center of Massekhet Ketubot. As is commonplace in the Gemara, there are also a wide range of other topics that are connected tangentially to the main themes of the tractate.