Solution above pretty much sums it up, but just finishing transferring playstationtrophies.org's solutions over to this site, as true trophies needs proliferation with more solutions.
This is easily done in the Combat Arena after you have beaten the game. Just give yourself infinite health and infinite magic and spam the magic ability, Scourge of Erinys. Press D-pad Left to activate this ability.
This trophy is actually insanely easy to get. Once you beat the game, enter the combat arena, spawn 4 infinitely spawning Minotaurs, and keep spamming Erinys' magic. I was able to get a 6100 hit combo doing this, and the trophy popped up - no problem.
Go to the arena, set your magic to Infinite. Set monsters health to Infinite, and turn off their Attack. Spam Erinys' magic. With this method, you can get 1,000,000 red orbs, which is the exact amount to purchase everything from Zeus' Temple. You should also have like a 10k hit combo.
All credit goes to orginal authors at playstationtrophies.org, and this is merely updating truetrophy fans with these guides.
http://www.playstationtrophies.org/game/god-of-war-ghost-of-...This is an additional video i found
This is PowerPYX's guide. All credit goes to his fantastic work.
http://www.powerpyx.com/guides/god_of_war_ghost_of_sparta.ht...