[IULIANUS libro LXXXIIII digestorum. ] §1.3.32.prDe quibus causis scriptis legibus non utimur, id custodiri oportet, quod moribus et consuetudine inductum est: et si qua in re hoc deficeret, tunc quod proximum et consequens ei est: si nec id quidem appareat, tunc ius, quo urbs Roma utitur, seruari oportet.
[JULIANUS, Digest, book 84] In those cases where we do not use written laws, that which has been introduced by manners and custom must be observed; and if in any matter this should be lacking, then that which is next and consequent to it; if not even that should appear, then the law which the city of Rome uses must be observed.
§1.3.32.1Inueterata consuetudo pro lege non immerito custoditur, et hoc est ius quod dicitur moribus constitutum.
Long-established custom is not undeservedly observed as law, and this is the law which is said to be established by manners.
nam cum ipsae leges nulla alia ex causa nos teneant, quam quod iudicio populi receptae sunt, merito et ea, quae sine ullo scripto populus probauit, tenebunt omnes: nam quid interest suffragio populus uoluntatem suam declaret an rebus ipsis et factis? quare rectissime etiam illud receptum est, ut leges non solum suffragio legis latoris, sed etiam tacito consensu omnium per desuetudinem abrogentur.
For since the laws themselves bind us for no other reason than because they have been accepted by the judgment of the people, justly also those things which the people have approved without any writing will bind all. For what difference does it make whether the people declare their will by vote or by facts and deeds themselves? Therefore, it is also most correctly accepted that laws are abrogated not only by the vote of the lawmaker, but also by the tacit consent of all through disuse.