Help to find out Hot/active, Neutral & Earth in this junction box in Australia, NSW
There are two very good methods for discriminating hot, neutral, switched, ground, etc. that are available to the home DYI handyman. You can use a voltmeter or a multimeter set to &quot;volts&quot;, or you can use a dummy load such as the ceiling lamp you just removed.
With the meter, you have to be careful not to touch the live wires with your fingers:

Turn the power off at the circuit breaker.
Disconnect everything from the wires, exposing the uninsulated ends. Spread the wires out so that none are near each other or near the junction box.
Turn the power on at the circuit breaker.
Carefully touch the meter probes to the exposed wire ends to test the voltage between each pair of wires in turn. Write down your observations.
Turn the power off at the circuit breaker.

With the dummy load, your are much safer, but you have to run back and forth between the work site and the circuit breaker panel:

Turn the power off at the circuit breaker.
Use two wire nuts to connect the dummy load to any pair of wires.
Turn the power on at the circuit breaker.
Observe whether the dummy load is powered, e.g. the lamp is lit et.al.
Turn the power off at the circuit breaker.
Repeat all the previous steps for each pair of wires in turn. Write down your observations.

In either case you should see these results:

Fault ground to neutral: 0 to 8 volts, lamp won't light (LED lamps may flicker).
Fault ground to hot or switched-hot: house line voltage (approx. 120 volts in U.S.A., may differ in Oz), lamp lights up.
Neutral to hot or switched-hot: house line voltage, lamp lights up.