Bar mitzvah reading (5)
I believe the answer is:
torah
'bar mitzvah reading' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for torah that I've seen before include "Jewish law" , "Pentateuch" , "Law as revealed to Moses (Judaism)" , "The whole body of Jewish religious literature" , "The law of God as revealed to Moses" .)