[POMPONIUS libro quarto ad Quintum Mucium. ] §46.3.80.prProut quidque contractum est, ita et solui debet: ut, cum re contraxerimus, re solui debet: ueluti cum mutuum dedimus, ut retro pecuniae tantundem solui debeat.
[POMPONIUS, in the fourth book on Quintus Mucius.] According as each obligation has been contracted, so also ought it to be dissolved: as, when we have contracted by a thing, it ought to be dissolved by a thing: as for instance when we have given a loan, so that an equivalent amount of money ought to be paid back.
et cum uerbis aliquid contraximus, uel re uel uerbis obligatio solui debet, uerbis, ueluti cum acceptum promissori fit, re, ueluti cum soluit quod promisit.
And when we have contracted something by words, the obligation ought to be dissolved either by a thing or by words; by words, as for instance when a formal release is made to the promisor; by a thing, as for instance when he performs what he promised.
aeque cum emptio uel uenditio uel locatio contracta est, quoniam consensu nudo contrahi potest, etiam dissensu contrario dissolui potest.
In like manner, when a sale or purchase or a letting has been contracted, since it can be contracted by bare consent, it can also be dissolved by contrary dissent.