[ULPIANUS libro uicensimo secundo ad edictum. ] §12.2.3.prAit praetor: 'Si is cum quo agetur condicione delata iurauerit'. eum cum quo agetur accipere debemus ipsum reum.
The praetor says: 'If the person against whom the action is brought should take an oath when the condition has been offered.' We ought to understand 'the person against whom the action is brought' as the defendant himself.
nec frustra adicitur 'condicione delata': nam si reus iurauit nemine ei iusiurandum deferente, praetor id iusiurandum non tuebitur: sibi enim iurauit: alioquin facillimus quisque ad iusiurandum decurrens nemine sibi deferente iusiurandum oneribus actionum se liberabit.
Nor is 'when the condition has been offered' added without purpose; for if the defendant took an oath when no one offered him the oath, the praetor will not protect that oath; for he took the oath to himself. Otherwise, any most shameless person, resorting to an oath without anyone offering it to him, would free himself from the burdens of actions.
§12.2.3.1Quacumque autem actione quis conueniatur, si iurauerit, proficiet ei iusiurandum, siue in personam siue in rem siue in factum siue poenali actione uel quauis alia agatur siue de interdicto.
Moreover, by whatever action anyone may be sued, if he takes the oath, the oath will benefit him, whether he is sued by an action in personam, or in rem, or in factum, or by a penal action, or any other action, or concerning an interdict.
§12.2.3.2Sed et si de condicione personae fuerit iuratum, praetor iusiurandum tuebitur: ut puta detuli iusiurandum et iurasti in potestate mea te non esse: tuendum erit iusiurandum.
But even if the oath was taken concerning the status of a person, the praetor will protect the oath; as, for example, if I offered you the oath and you swore that you were not in my power, the oath must be protected.
§12.2.3.3Unde Marcellus scribit etiam de eo iurari posse, an praegnas sit mulier uel non sit, et iuriiurando standum: denique ait, si de possessione erat quaestio, seruari oportere, si forte quasi praegnas ire in possessionem uolebat et, cum ei contradiceretur, uel ipsa iurauit se praegnatem uel contra eam iuratum est: nam si ipsa, ibit in possessionem sine metu, si contra eam, non ibit, quamuis uere praegnas fuerit: proderitque, inquit Marcellus, mulieri iuranti iusiurandum, ne conueniatur quasi calumniae causa uentris nomine fuerit in possessionem neue uim patiatur in possessione.
Hence Marcellus writes that an oath can also be taken on this point, whether a woman is pregnant or not, and that the oath must be stood by. Furthermore, he says that if the dispute was about possession, it ought to be observed, if by chance she wished to enter into possession as if pregnant and, when she was contradicted, either she herself swore that she was pregnant or it was sworn against her; for if she herself swore, she will enter into possession without fear, but if it was sworn against her, she will not enter, even though she was truly pregnant. And Marcellus says that the oath will benefit the swearing woman, so that she may not be sued on the ground of having entered into possession in the name of the unborn child for the sake of trickery, nor suffer violence in possession.
sed an iusiurandum eo usque prosit, ut post editum partum non quaeratur, ex eo editus sit an non sit cuius esse dicitur, Marcellus tractat: et ait ueritatem esse quaerendam, quia iusiurandum alteri neque prodest neque nocet: matris igitur iusiurandum partui non proficiet: nec nocebit, si mater detulerit et iuretur ex eo praegnas non esse.
But Marcellus discusses whether the oath benefits to such an extent that, after the child is born, there should be no inquiry whether the child born is or is not his whose child he is said to be; and he says that the truth must be inquired into, because an oath neither benefits nor harms another person. Therefore, the oath of the mother will not benefit the child; nor will it harm him, if the mother offered the oath and it was sworn that she was not pregnant by him.
§12.2.3.4Iurari autem oportet, ut delatum est iusiurandum: ceterum si ego detuli ut per deum iurares, tu per caput tuum iurasti
But an oath must be taken as it has been offered; but if I offered that you should swear by God, and you swore by your own head,