proponis: proclaim, but with a suggestion of pledge rather than of mere prophecy; cf. Caes. BG 5.58.5 “magna proponit iis qui occiderint praemia” ; Cic. Tusc. 5.20 “praemium proposuit qui invenisset novam voluptatem” .
 di magni: here a true invocation, and not, as in Catul. 14.12 and Catul. 53.5, a mere expletive. Ellis compares Cic. Att. 16.1.6 “di faxint ut faciat ea quae promittit, — commune enim gaudium, — sed ego” , etc.
 perducere: Lachmann, following the early Italian editors, would read producere, on the ground that perducere occurs only when a limit is definitely set. But the MSS. of Prop. 1.3.39 “o utinam tales perducas, improbe, noctes” seem to support this reading, and the omitted limit is easily supplied from tota vita.