This aria, like many of the baroque and early classical periods, is known not from its original operatic source, but from publication in a collection edited by Parisotti, and published in the late 19th century. This collection quickly became a common source for salon and for recital music, and today it is the rare vocal recital which doesn’t contain one or two of these arias as an introduction and warm-up.

This aria has long, graceful lines, with many changes in dynamics (volume), which allow a singer to display breath control and tone. The words are very simple, as in many of the baroque arias. "My dear treasure, at least believe me, without you, my heart mourns. Your faithful one is always sighing–cease, cruel one, such harshness." The aria then repeats, usually with vocal ornamentation at the singer’s discretion.

(source: Allmusic.com)