Livy Ab Urbe Condita - 21.22

Ab Gadibus, Carthaginem ad hiberna exercitus rediit; atque inde profectus praeter Onussam urbem ad Hiberum per maritima ora ducit.

From Gades, he returned to Carthage, to the winter camp of the army; and having set out from there he leads them beyond the city Onussa to the Ebro on the seacoast.

Ibi fama est, in quiete qui se ab Jove visum diceret ducem in Italiam Hannibali missum; proinde sequeretur neque usquam a se deflecteret oculos.

There is a rumor that in a dream there was a man who said that he seemed to have been sent by Jove as a leader and into Italy for Hannibal. Let him follow, and let him not turn his eyes away from himself.

Pavidum primo, nusquam circumspicientem aut respicientem, secutum; deinde cura ingenii humani cum, quidnam id esset quod respicere vetitus esset, agitaret animo, temperare oculis nequivisse;

At first, he was fearful, he followed, neither looking around nor looking back. Then, with the curiosity of human nature, whatever it is, which he had been prohibited to look back at, it stirred up his mind, he was unable to control his eyes;

 tum vidisse post sese serpentem mira magnitudine cum ingenti arborum ac virgultorum strage ferri ac post insequi cum fragore caeli nimbum.

then he saw behind himself a serpent of marvelous magnitude with destruction of trees and shrubs and he followed behind with a crash of clouds in the sky.

Tum quae moles ea quidue prodigii esset quaerentem, audisse vastitatem Italiae esse; pergeret porro ire nec ultra inquireret sineretque fata in occulto esse.

Then, asking what mass is this or what is this prodigy, and he heard that it was the destruction of Italy: that he was to go on further and to not inquire further and to accept that the fate was in private.