Of course, now that I've started law school my mind is turned ever towards the things I'm reading about and talking about pretty much every waking hour of every single day. What's this latest topic? Why, it may be based on the ancient and modern laws of CONTRACT.
Ancient laws of contract (mostly what we would call common law outside of the regions influenced by Justinian's Roman canon) focused on a special, ritual space that separated out the act of signing the contract from the acts of every day life. These were liminal moments, powerful moments, when binding legal documents took force. IN modern contract law, you can make a contract simply by assenting to an offer verbally (as long as its not a sale of goods; Statue of Frauds covers that). Not so in the ancient and medieval world.
Contract as Oath
I. Seriousness of the Undertaking
II. The Seal
III. The Witnesses
IV. The Oath and Punishments
Contracts in the ancient, medieval, and particularly the post-Enlightenment world were entered into with a sense of seriousness. Ritual surrounded them. Documents were prepared, witnesses gathered, and oaths sworn. The written instrument was merely the expression of the contractual bargain. This is, perhaps, one of the reasons why medieval abbots felt no shame in producing what we would commonly today call "fake" charters that detail sales of land to the abby. The abby knows the land is theirs—thus, the false contract merely confirms a deeper truth.
People did not sign contracts in a lighthearted or casual way. Promises were important, and thus swearing promises were often accompanied by involving the Gods (or God in Christian Europe). This illustrates the ease with which contractual agreements and promises are actually put aside (very easily, since there's no supernatural force behind them) in stark contrast to how difficult society wishes it were to put a contract or agreement aside.
II. The Seal
It is no longer true today that the written instrument of a contract really even requires signatures. The paper is something external. However, in the heyday of the Serious Contract it was required for every party bound by it to make their mark with a seal. In the Middle Ages this could take place in the form of a signature, but the entire document was usually sealed with some seal or other. It was very common (for extremely important documents) for the local bishop or perhaps even the regional king to imprint his seal in wax upon your parchment.
The seals (signature + imprint) give the contract validity.
III. The Witnesses
The gathering of and signing of witnesses was extremely important in certain types of charters. The more important your witnesses were, the more important your charter. You want your bishops and high ranking church members to witness for you because that speaks leagues about your own personal authority and respect.
IV. The Oath
Many contracts also included a number of cursing clauses, damning those who break the promise. It wasn't uncommon for charters, for example, to wish horrific punishments on people who alienated the land granted to an abby. Charter-cursing forms an entire subfield of study and is extremely inventive.
This supernatural sword of Damocles exists to lend force and weight to what is otherwise really just a piece of parchment and what, in reality, can be ignored with impunity. This element also bears a strong relationship to the verbal oath given in pre-literate societies.
V. So What?
So nothing, asshole. Why are you so rude? This is all interesting stuff to spice up the world of your D&D game. Contracts in the 10th Age, for example, must be sealed by an "official witness," that is a member of the Temple of Miles, so they are seen by the God of Law and Smithcraft, Haeron the Hammerer. This element of the semi-divine mirrors the ways in which medieval contracts invoked God.
You can do that too, if you want. It helps take your game away from the humdrum world of the mundane everyday and into the fantastic past.