Why must wait() always be in synchronized block

Question

We all know that in order to invoke Object.wait(), this call must be placed in synchronized block, otherwise an IllegalMonitorStateException is thrown. But what\'s t

Answer 1

as per docs:

The current thread must own this object's monitor. The thread releases ownership of this monitor.

wait() method simply means it releases the lock on the object. So the object will be locked only within the synchronized block/method. If thread is outside the sync block means it's not locked, if it's not locked then what would you release on the object?