Are there any classical commentaries on the Vidui (short and long)? I see explanations in the Koren and Artscroll, but those are mostly modern.
2 Answers
Siddur Torat Ḥayyim by Mosad HaRav Kook is a good place to look for several Rishonic commentaries on the long viduy. The second volume contains a line-by-line commentary by Abudarham and the Rokeaḥ, along with sporadic comments from Ra'avan, Sefer HaManhig, and R. Yehudah ibn Yakar.
It seems that the Abudarham's commentary can be found on Sefaria here, but I don't know its completeness/accuracy.
Two ones I know of are:
The Chida has a breakdown on each of the words in his Sefer Vidui Gadol
In Chapter 143 of the Chayei Adam there is a famous commentary - again there is an explanation for each word/individual part.