Siegfried's "hearing" of the forest murmurs in the orchestra actually continues a mode of musical discourse that has already been established in Die Walkure (see, for example, Siegmund's relationship with the sword
Notung, with the springtime moonlight and with Sieglinde, in Die Walkure 1.3).
In this scene Siegmund (Schneider) gets the girl, Sieglinde (Porackova), the sword, called "
Notung! (Needy) to dispatch the nasty dragon Fafner, the gold watch and everything, which in this case consists of the knowledge that the girl is actually his sister, but nonetheless destined to be his wife and mother of superhero Siegfried.
Mime is eventually persuaded to tell Siegfried the truth about his parents, and he shows him the broken sword
Notung. Wotan arrives in the form of the Traveller, and challenges Mime to a riddle contest.