Every obligation is dissolved by the payment of what is due; or where a party gives one thing instead of another with the creditor's consent. Nor does it make any difference who makes the payment, whether he who owes the debt or another for him; for he is discharged by the payment of another, whether that payment was made with the knowledge of the debtor or whether he was ignorant of it, or even if it was made against his will. Again, if the principal pays, those also who have become sureties for him are likewise discharged; and the same rule applies where, on the other hand, the surety makes payment; for not only is he himself discharged but the principal as well.

(1) An obligation is also extinguished by a release which is a fictitious payment. For if Titius wishes to remit what is due to him on a verbal obligation this can be done by permitting his debtor to speak as follows: "Do you admit that you have received what I promised you?" and by Titius answering "I do". This acknowledgment can also be made in the Greek language, provided it is expressed as is usually done in Latin. As We have stated, only verbal obligations can be dissolved in this way, but no others; for it seemed consistent with reason that an obligation incurred by words could be dissolved by means of other words. Nevertheless, what is due for some other cause can be turned into a stipulation, and be extinguished by a release, and just as a debt can be legally paid in part, so also can the release of a debt be made in part.

(2) A stipulation has been devised which is ordinarily designated the Aquilian, by means of which obligations of every kind are converted into stipulations and are then discharged by a release. For the Aquilian stipulation effects the novation of all obligations, and was expressed in the following language by Callus Aquilius: "Whatever you are obliged or shall be obliged to give me, or to do for me, for any reason, at the present, or at some future time; and for whatever cause I have, or shall have an action, a petition, or a prosecution against you; and whatever property belonging to me you have, hold, possess, or have possessed, or by means of fraud have brought it about that you no longer possess, and no matter what sum each of these things may be worth, Aulus Agerius has stipulated and Numerius Negidius has bound himself to pay said sum of money". Again, on the other hand, Numerius Negidius asked Aulus Agerius: "Do you acknowledge that you have received all for which I have this day obligated myself by the Aquilian stipulation?" And Aulus Agerius replied: "I have it, and I have entered it as received".

(3) Moreover, an obligation is extinguished by novation; as, for example, if what you owe to Seius is stipulated by him to be paid by Titius; for by the intervention of a new person a new liability arises, and the first one is dissolved by being transferred to the last; so that sometimes, although the last stipulation may be void, still the first one is dissolved by virtue of the novation; for instance, if Titius should stipulate with a ward, without the consent of his guardian, that he shall pay what you owed him, for in this case the property is lost; as the original debtor is discharged, and the subsequent obligation is void. This principle does not apply where anyone stipulates for payment by a slave; for then the original debtor remains liable, just as if no one had made a stipulation afterwards.

But if you make a stipulation with the same person that you did before, novation only takes place where there is something new in the subsequent stipulation; for example, if a condition, or a time for payment, or a surety is either added or omitted. What We have stated with reference to a novation occurring where a condition is added, must be understood in this way, namely; that We declare a novation to have been made if the condition is fulfilled, but, on the other hand, if it fails, the original obligation remains in force. But although it was established among the ancients that a novation occurred when the second obligation was entered upon with the intention of bringing it to pass; still a doubt arose as to when it was to be deemed that this was done with a view to causing a novation; and some authorities introduced certain presumptions in some cases, and others in others; and therefore We have promulgated a Constitution, which expressly sets forth that novation can only take place when it has been expressly stated by the contracting parties that they have come to an agreement with respect to a novation of the original obligation; otherwise the latter shall stand, and the second one shall be added thereto; so that an obligation will arise from each transaction, according to the terms of Our Constitution, which you may ascertain more fully by the perusal of the same.

(4) In addition to this, such obligations as are contracted by consent are dissolved by change of mind; for if Titius and Seius agree that Seius shall have the Tusculan estate for the sum of a hundred aurei; and then, before the contract is executed, that is before the price has been paid or the land transferred, it should be agreed between them to withdraw from this purchase and sale they are reciprocally released from liability. This same rule applies to leasing and hiring as well as to all contracts entered into by consent, as has already been stated.