Clone Corridor posted an examination of the funeral scene music used in both TPM and ROTS:
Aside from bringing back the solemnity of Qui-Gon’s funeral, this is also the third time within the Prequel Trilogy that John Williams uses Sanskrit as his language choice. The first time is during the ‘Battle of Fates’ between Qui-Gon, Darth Maul and Obi-Wan Kenobi. The second and third time are the double uses of the Funeral-theme. Each of these instances is a moment in which Light and Dark come together and cause destruction. Rather than choose pre-existing Sanskrit texts and adapting them to his own liking, Williams had an Celtic poem translated for the ‘Battle of Fates’ and chose lyrics from that. For the Funeral-theme he had the line ‘Death’s long sweet sleep’ loosely translated.