[POMPONIUS libro undecimo ad Sabinum. ] §21.2.29.prSi rem, quam mihi alienam uendideras, a domino redemerim, falsum esse quod Nerua respondisset posse te a me pretium consequi ex uendito agentem, quasi habere mihi rem liceret, Celsus filius aiebat, quia nec bonae fidei conueniret et ego ex alia causa rem haberem.
[POMPONIUS, On Sabinus, Book Eleven] If I have bought back from the owner a thing which you had sold to me as belonging to another, Celsus the son used to say that the opinion which Nerva had given—namely, that you, by bringing an action on the sale, could recover the price from me, as if it were permitted for me to hold the thing—is false, because it would neither agree with good faith, and I would hold the thing from another cause.
§21.2.29.1Si duplae stipulator ex possessore petitor factus et uictus sit, quam rem si possideret retinere potuerit, peti ita autem utiliter non poterit, uel ipso promissor duplae tutus erit uel certe doli mali exceptione se tueri poterit, sed ita, si culpa uel sponte duplae stipulatoris possessio amissa fuerit.
If the stipulator of the double has become a plaintiff instead of a possessor and has been defeated—which thing, if he had possessed it, he would have been able to retain—but it cannot be sued for effectively in this way, the promisor of the double will either be safe by the law itself or at least will be able to defend himself by the plea of fraud; but only if the possession was lost through the fault or voluntary act of the stipulator of the double.
§21.2.29.2Quolibet tempore uenditori renuntiari potest, ut de ea re agenda adsit, quia non praefinitur certum tempus in ea stipulatione, dum tamen ne prope ipsam condemnationem id fiat.
Notice can be given to the seller at any time to be present for the conduct of the matter, because no definite time is prescribed in that stipulation, provided, however, that this does not happen close to the judgment itself.