This very brief Wikipedia article contains the original German text of the aria and an English translation. I’d definitely suggest listening to the aria with the translation in front of you. It’s much more meaningful if you understand what’s being sung.

Introduction

“Liebestod” ([ˈliːbəsˌtoːt] German for “love death”) is the title of the final, dramatic music from the 1859 opera Tristan und Isolde by Richard Wagner. When used as a literary term,liebestod (from German Liebe, love and Tod, death) refers to the theme of erotic death or “love death” meaning the two lovers’ consummation of their love in death or after death. Other two-sided examples include Pyramus and Thisbe, Romeo and Juliet, and to some degree Wuthering Heights. One-sided examples are Porphyria’s Lover and The Sorrows of Young Werther. The joint suicide of Heinrich von Kleist and lover Henriette Vogel (de) is often associated with the Liebestod theme.

The aria is the climactic end of the opera as Isolde sings over Tristan’s dead body.

Partial Text