Difference Between Oratorio, Cantata and Opera

Oratorio and cantata were two genres that re-emerged in the first half of the eighteenth century. They were already important musical alternatives to opera by the mid-seventeenth century, but differed in nearly every respect from the genres of the same names found in the early eighteenth century. As genres late in the period, they both bespoke the traditions from which they originally sprang and permitted new recombination of the musical elements of these same traditions.
The oratorio and cantata of the eighteenth century were both linked, unlike opera, to religious themes. Although intended for very different uses and circumstances of performance, all three genres contained musical commalities. Not surprisingly, the three genres would share similarities given the restricted number of available forms. On a superficial level, the three genres could be said to differ in delivery and intent rather than in musical content. All three genres featured recitative, solo and duet arias, choral movements, many of the same forms, and even dance elements.
The opera is based upon one of the variants of the timeless story of love and loss and involves staging. The oratorio is also based upon a story, but a sacred one with Biblical origins rather than a secular one. Oratorio is not staged and is not used as part of worship. A significant feature is the use of the chorus as narrator. The cantata addresses a religious topic, but it is not narrative. Rather it is a collection of commentary set to music, and the cantata is used in worship. In the religious music orb, the work methods of the two most important composers, G.F. Handel and J.S. Bach differed extensively.
As early as the middle of the seventheenth century, the aria had supplanted the recitative as the most important musical component of the opera. This hierarchy remained intact throughout the Baroque period. The earlier forms of the aria, including strophic, ostinato, and dance, continued to be used, but in the late