I'm in THE INFIDEL'S TOMB that is totally blocked

Hint 1 of 7:

Did you examine the STEP?

Hint 2 of 7:

CLIMB ON it.

Hint 3 of 7:

Did you search the STATUE?

Hint 4 of 7:

Did you notice a SLOT anywhere?

Hint 5 of 7:

Put something in the slot.

Hint 6 of 7:

You need to have come to THE WALL with a dagger to succeed here.

Hint 7 of 7:

Take a dagger and PUT IN the slot.