Once inside the temple, recover your magic and/or health as necessary then open the door. Once inside, you have to defeat the Cerberus. After taking out the Cerberus, continue forth and collect the red orbs from the red chests ahead.
Pull the ramp ahead then head to the statue emitting green mist to the left. This will change the time. Go past the main door and break down the door to the far right to find two chests containing a Gorgon Eye and a Phoenix Feather.
Delphi Temple Gorgon Eye and Phoenix Feather
If the time reverts to normal, touch the green mist again then destroy the main door this time. Continue forth until you reach the next hall. After the scene, step on the green mist then take the stairs to the right first. Destroy the door and follow the path until you reach the next hallway. Defeat the enemies to unblock the pathways.
Now in the middle of the hallway is a movable statue. Grab it and push it towards the first room to the right. At the upper level of the room lies two red and white chests. Push the statue under the metal grate to the right then touch the green mist to make the grate fall down on the statue's head. Jump on it to reach the goodies.
Delphi Temple Gorgon Eye and Phoenix Feather, East
Head to the next room in the end of the hallway to find two red chests and a health chest. You can also destroy the objects in the room for extra red orbs. Backtrack to the starting point this time.
From the entrance, step on the green mist and take the stairs to the left. Destroy the door and continue to the hallway. Here you'll encounter a lightning banshee. Take it out to remove the barricades. There's a couple of collectibles found in the first room to the left.
First, grab the movable statue in the middle-right of the hallway. Push it inside the lower left room then place it on top of the pressure plate. Now step on the green mist, push the statue out of the pressure plate then head towards the gate. Once the time returns to normal, push forward to enter the next room. Grab the Gorgon Eye and Phoenix Feather inside, as well as two red chests and a lever to disable the gate.
Delphi Temple Gorgon Eye and Phoenix Feather, West
Continue to the next room and open the red chest to the left. Step on the mist and jump through the hole on the floor to reach the lower level. Continue forth to reach the next chapter.