The Jedi Temple is monumental in scale. See those steps leading up to the statues near the entrance? They're not steps; they're landings. The little dots that look like ants are people. If you count carefully there are 12 flights of steps, broken by 11 intermediate landings between them, just to get up to the level where the enormous statues tower above you. Then there are a further 10 flights of shallower steps broken up by more landings to get up to the actual entrance level of the temple.

Clearly this is some sort of endurance test. Anyone who can make it up all those stairs is physically fit enough to be a Jedi.

Transcript

Yoda: {Sally} So Anakin, how are you going?
Anakin: In a nutshell, I could count myself a king of infinite space... were it not that I have bad dreams.
Yoda: Leave a light on, you should.
Anakin: The Sith press on my thoughts. I fear the jaws of darkness may devour us.
Yoda: Fear. Mmmm. The path to the Dark Side, this is. Careful you must be.
Anakin: We must find the Sith Lord traitor.
Yoda: Oooh. Who do you think it is?
Anakin: I have my suspicions.
Yoda: Tell me!
Anakin: I don't want to name anyone just yet.
Yoda: It's you!
Anakin: What? Er... No. Of course not. Who told you that?
Yoda: Hee hee! Just testing. No, it's obviously Obi-Wan.
Obi-Wan: Sally!