Legal Definitions - causa promissionis

causa promissionis

Causa promissionis is a principle, primarily found in ecclesiastical law (church law), which states that an informal promise or undertaking is not legally binding unless it is supported by a valid reason or justification. Essentially, for a promise to create an obligation, there must be a good "cause" or underlying purpose for making it.

Here are some examples illustrating this concept:

• Imagine a situation where a church member casually tells a friend, "I'll help you paint your house next weekend if I have time." This is an informal promise. If the church member later decides they are too busy and doesn't show up, the friend likely cannot compel them to paint. Under the principle of causa promissionis, this initial promise lacked a formal agreement or a clear "cause" (such as a reciprocal promise or a specific benefit to the promisor) that would create a binding obligation. It was a casual offer of goodwill, not a firm undertaking with a specific underlying reason that would make it enforceable.

• Consider a parishioner who, during a casual conversation, tells their priest, "I promise to donate a significant sum to the church's new building fund next year." This is an informal promise. If, later, the parishioner faces unexpected financial hardship and cannot make the donation, the church might not be able to legally enforce this promise under causa promissionis. While there was a good intention, the promise itself, being informal and without a formal pledge or specific conditions attached, might be considered to lack the kind of "cause" that creates a binding obligation in ecclesiastical law, especially if circumstances change. The underlying reason for the promise (the ability to donate) has changed, potentially removing the "good cause" for enforcement.

• Conversely, consider a person who makes a solemn vow during a religious ceremony to undertake a specific charitable act for the community, witnessed by others and perhaps recorded in some manner within the religious institution. In this instance, the "cause" for the promise is the spiritual commitment, the public declaration, and the religious context itself. Under causa promissionis, this promise would likely be considered to have a sufficient "good cause" to create a moral or even ecclesiastical obligation, making it binding on the individual within the church's framework, even if it's not a civil contract. The underlying reasons of religious duty and public commitment provide the necessary "cause" for the promise to be obligatory.