"Solenne in quest'ora" from Act 3 of La Forza del Destino (1862), sung by Placido Domingo. In this aria, a dying man asks his best friend: "Burn my letters when I die." Agreeing on this, the two men sing a duet.
Just in case you thought "delete my online history when I die, bro" happened with the internet. Nope, we're all worried about our families finding our dirt.