A verbal obligation is contracted by a question and answer, when we stipulate for something to be given to us or done for us. From this proceed two actions-at-law, a personal action for recovery, where the stipulation is certain, and an action on contract where it is uncertain. A stipulation is called by this name for the reason that among the ancients stipulum signified firm, being derived perhaps from stipes.

(1) In a transaction of this kind the following words were formerly used: "Do you agree?" "I do agree." "Do you promise?" "I do promise." "Do you pledge your faith?" "I do pledge my faith." "Do you bind yourself?" "I do bind myself." "Will you give?" "I will give." "Will you do so-and-so?" "I will do so-and-so." But whether the stipulation is stated in Latin, Greek, or any other language, does not matter, if both the contracting parties understand it; nor is it necessary for both of them to make use of the same language, but it is sufficient if a suitable answer is made to the question; and, moreover, two Greeks may contract an obligation in the Latin language. These solemn words, however, were indeed formerly used, but afterwards the Leonine Constitution was promulgated, which dispensed with the verbal formality, and required that only the meaning and intention should be understood on both sides, no matter in what language they were expressed.

(2) Every stipulation is made either absolutely, with reference to a certain time, or under some condition. It is made absolutely, for example, "Do you agree to give five aurei?" and they can be demanded without delay. With reference to a certain time, when the stipulation is made with a day mentioned on which the money is to be paid, as, for instance: "Do you agree to pay ten aurei on the next Kalends of March?" What We stipulate to do at a certain time is in fact due immediately, but cannot be demanded until the day arrives; nor indeed can it be demanded on the very day provided for by the stipulation, because the entire day should be granted to the discretion of the party who is to make payment; for it is not certain that it has not been paid on the day on which it was promised until that day has gone by.

(3) But if you stipulate as follows: "Do you agree to pay me ten aurei every year as long as I live?" the obligation is understood to be absolute and continuous, because it cannot be due for a time; but the heir, if he brings suit, will be barred by an exception on the ground of contract.

(4) A stipulation is made under a condition when the obligation is deferred until some event takes place, so that the stipulation becomes operative if something is, or is not done; as, for instance: "Do you agree to pay me five aurei if Titius becomes Consul?" and where a man stipulates as follows: "Do you agree to make payment if I do not go up to the Capitol?" it will be just as if he had stipulated that he should be paid when he dies. Under a conditional stipulation there is only a hope that a debt will become due, and we transmit that hope to our heir, if death seizes us before the condition is fulfilled.

(5) Places are also inserted in a stipulation, as, for example: "Do you agree to pay at Carthage?" which stipulation, although it seems to be made absolutely has, nevertheless, so long a time attached to it as the party promising would need in order to pay the money at Carthage; therefore, if anyone stipulates at Rome: "Do you agree to make payment at Carthage to-day?" the stipulation is void, as the promise given in reply is impossible.

(6) Conditions which relate to past or present time either render the obligation invalid immediately, or do not defer it at all, as, for example: "Do you agree to make payment if Titius has been Consul, or if Mævius is living?" For if these things are not true, the stipulation is worthless; but if they are true, it becomes valid at once; for such matters as are certain in the nature of things do not postpone an obligation, although they may be uncertain so far as Our knowledge of them is concerned.

(7) Not only can property be the object of a stipulation, but deeds, also as where We stipulate for some act to be performed or not performed; and it is best to add a penalty to stipulations of this kind, so that the amount involved in the stipulation may not be uncertain, and it may become necessary for the plaintiff to prove the amount of his claim; and, therefore, where anyone stipulates for something to be done, a penalty ought to be added thus: "If it is not done in this way, do you agree to pay ten aurei by way of penalty?" But if he stipulates by one and the same statement that certain things are to be done, and certain others are not to be done, a clause of this description should be added: "If anything is done in violation of this contract, or anything is done which is not in compliance with it, do you agree to pay ten aurei by way of penalty?"