hang on , yes, the hoplites had the large shield (Hoplon ) and that is what gives the name ' Hoplite'

However, goliat had a large shild and the armour , but was using a javeline as well as a thrusting spear. A shildbearer carried is shield in front of him , IIRC. Now, maybe the philistines used similar armour in a different sort of way. He seems to have been a champion of sorts and the combat was decided by pitting champion against champion , rather in the manner of the epics described in the trojan war.