What is the primary function of the overture in an oratorio?

The primary function of the overture in an oratorio is to introduce the themes. The overture serves as a musical prelude that sets the tone for the work, providing the audience with an initial glimpse of the musical material and motifs that will be developed throughout the performance. It often encapsulates the emotional landscape and thematic content of the entirety of the oratorio, preparing listeners for the narrative and musical experience that follows.

The overture functions to engage the audience's attention right from the start, establishing the context and atmosphere in which the subsequent musical and vocal pieces will unfold. This introductory role is crucial in an oratorio, where the dramatic elements conveyed through music and text rely heavily on themes introduced during the overture.