The genitive with an infinitive is rather frequent in Koine Greek to
express purpose; it means exactly the same thing that a hINA + subjunctive
clause would do. Originally there was a preposition (hENEKA) requiring the
genitive that meant "for the sake of"; this came gradually to be omitted
and the articular infinitive in the genitive case came to be a construction
for purpose.
SO: When you see a TOU + infinitive (and no countermanding indicators), you
can usually be sure that it's an infinitive of purpose; translate the
infinitive as "in order to xxx". So here, "in order to dishonor their own
bodies ..."
Carl W. Conrad
Department of Classics/Washington University
One Brookings Drive/St. Louis, MO, USA 63130/(314) 935-4018
Home: 7222 Colgate Ave./St. Louis, MO 63130/(314) 726-5649
cwconrad@artsci.wustl.edu OR cconrad@yancey.main.nc.us
WWW: http://www.artsci.wustl.edu/~cwconrad/