tribunos aerarios, probably revenue officers of some kind, but not much is known about them.
scribas, etc., the permanent government clerks, a certain number of whom were attached to each magistrate. On this day (Dec. 5) the quaestors for the next year entered on their office, and the scribae had to draw lots to decide which quaestor they should severally attend. This drawing took place at the treasury, which was in the Temple of Saturn at the west end of the Forum, in full view of the Temple of Concord. Hence tr.: 'the entire body of clerks also, who having been brought to-day by chance to the treasury have I see been diverted from the anticipation of the lot to thoughts of the public safety.'
ingenuorum, 'freeborn citizens,' opposed to libertini, who though citizens were not freeborn.
sit, not subj. after 'cum' (which = 'not only'), but consecutive.
operae pretium est, 'it is worth while.'
sua virtute, etc., 'who by their own exertions have won the advantages of our citizenship'; because only those would be manumitted whose industry and energy deserved it.
qui modo sit . . . qui non, etc., the first relative clause limits the subject ('servus'); the second is consecutive. 'There is no slave,—none at least whose condition of servitude is bearable—who does not,' etc. Cf. in Pisonem §45 'Nemo denique civis est, qui modo se civem esse meminerit, qui vos non oculis fugiat.'
voluntatis, gen. after 'tantum.'