The key circles round to the lock
A lock which is known needs no key
A door that only faces inward  
On the outside has nothing to see

To open the way is to find yourself
Staring at the firmly locked door
To find the key is to notice
You've not needed a key here before

The way to ascend is much lower
Not up or through but behind  
So that door and its lock will remain
Until we let them leave our mind