[PAULUS libro tertio ad Sabinum. ] §12.6.6.prSi procurator tuus indebitum soluerit et tu ratum non habeas, posse repeti Labeo libris posteriorum scripsit: quod si debitum fuisset, non posse repeti Celsus: ideo, quoniam, cum quis procuratorem rerum suarum constituit, id quoque mandare uidetur, ut soluat creditori, neque postea exspectandum sit, ut ratum habeat.
[PAULUS, On Sabinus, book 3.] If your agent has paid what is not due and you do not ratify it, Labeo wrote in his posthumous books that it can be recovered; but if it was a debt, Celsus says it cannot be recovered. For this reason, because when anyone appoints an agent for his affairs, he is also deemed to mandate this, that he pay the creditor, and one should not afterwards wait for him to ratify it.
§12.6.6.1Idem Labeo ait, si procuratori indebitum solutum sit et dominus ratum non habeat, posse repeti.
The same Labeo says that if what is not due is paid to an agent and the principal does not ratify it, it can be recovered.
§12.6.6.2Celsus ait eum, qui procuratori debitum soluit, continuo liberari neque ratihabitionem considerari: quod si indebitum acceperit, ideo exigi ratihabitionem, quoniam nihil de hoc nomine exigendo mandasse uideretur, et ideo, si ratum non habeatur, a procuratore repetendum.
Celsus says that he who pays a debt to an agent is immediately discharged, and ratification is not considered; but if the agent has received what is not due, ratification is required for this reason, because the principal is deemed to have mandated nothing regarding the collection of this claim, and therefore, if it is not ratified, it must be recovered from the agent.
§12.6.6.3Iulianus ait neque tutorem neque procuratorem soluentes repetere posse neque interesse, suam pecuniam an pupilli uel domini soluant.
Julian says that neither a guardian nor an agent, when they pay, can claim recovery, and it makes no difference whether they pay their own money or that of the ward or principal.