You are right, "hortatory subjunctive" is synonomous with "cohortative
subjunctive". You also confirmed a nagging suspicion--"hortatory" is by far
the prefered description. You have helped me realize that "cohortative" does
not communicate.
Neither is it found in any of the grammars on my shelves.
However, James Efrid refers to this usage of the 1st person plural
subjunctive as "cothortative" in A Grammar for NT Greek (Abingdon, 1990), p.
51. Also Voelz in Fundamental Greek Grammar (Concordia, 1986), p. 188.
Nigel Turner's Grammar of NT Greek in 1963 refers to it as the "Hortative"
and Winer in the 19th century refers to it as the "adhortative." A. T.
Robertson labeled it "volitive."
I consulted with my supervisor at Denver Seminary, Dr. Craig Blomberg. As
far as we can figure, I "caught it" from him. He also traced the usage to
Doug Moo in his Trinity class notes.
I think it stuck with me as a preference because the "co" expresses the 1st
person plural, and I liked the alliteration.
Cindy Westfall
Post-graduate student
Denver Seminary