When searching for the meaning of the phrase ברפידם I found out that the commentators read this as an acronym. But I found different of these: One says it's an acronym for rafu yadeyhem (or rifui yadayim ריפוי ידים) Another it's an acronym for rafu yedeyhem min Hamitzvot While others say its's rafu yedeyhem mi'divrei Torah or min ha'Torah
I'm looking for their sources and the reason for their differences
The vast majority of commentators (e.g. Rashi, Chizkuni, Rabbeinu Bachya/Bechaye, Or Hachaim) use the term "Rafu Yedeihem Min Hatorah", which is found in Mechilata Derashbi, Mechilta Derabbi Yishmael, Tanchuma, and Yalkut Shimoni, all here (Shemos 17). Keli Yakar to Shemos 17:8 notes that this is because they were lacking water at Refidim, and Torah is compared to water.
There are a few Midrashic texts which have either Mitzvos or Aveiros, but they do not seem to be quoted by commentators, or come from similar mainstream sources.
(See this search for some details on the above.)
