What's to understand in this command is that we have the inner authority to do this revocation process start to finish. 
We are Sovereign, Awesome Creator Beings mind controlled into agreeing that we are simply "human" or otherwise deceived into agreeing to the limitations we now find ourselves in.

What's happening in this command is that (as EGO-SELF or just "regular you") you are choosing to acknowledge and allow Your Greater Self, Your Divine Inner Self to step forward and take action for ego-you.  

And as we 'let go' to some degree of being 'regular ego-self' we are allowing ourselves to experience ourselves from this greater perspective or level of Divine, All Powerful Creator Self.

All we have to do is state it and imagine it.  As in, state... "From the Inner Authority of My Sovereign Self I declare..."

And this is enough for Sovereign Self to 'step in' and take action on behalf of Self as Ego-self.
And in fact what has happened to get you in this limited "Ego-Self" state of mind and state of Consciousness is that Sovereign Self, the Real You has shifted in consciousness over time and has become EGO-Self.

Sovereign Self, the Real You has shifted in consciousness over time in such a way as to add many limitations to the subconscious mind.  This aspect of Mind that we are talking about here is of course complex and complicated and has many many aspects to it.  The aspect we are most concerned with here in boot camp is that part that has all the physical universe survival issues in it, along with all the agreements that some how pertain to life and experience in this Universe of Polarity and Duality... in other words this Physical Universe.

So it's this aspect of Your Mind makes you the Quirky Individual that you are today.  

What's in this part of your mind is all your imaginings, visualizations, mental images, memories, beliefs, emotional triggers, agreements, decisions, desires, fears, worries, concerns, problems, limitations, value systems, rules for living, psychosomatic illnesses, and just all kinds of 'stuff'.  And it is this part of your mind that you are imprisoned in.  

You are not imprisoned in the world or universe, you are imprisoned in and by your mind.  

This world actually is 'in your mind' too.  This world and universe is in your mind, its a visualization running on automatic, or a dream running on automatic that you can't escape from.  But it's all in your mind.  But the good new is that your mind is only a problem or issue because you agree that it is.  Or another way of saying it is that you (as Ego-Self) can completely manage this part of your mind session by session by declaring "From the Inner Authority of Your Sovereign Self you declare all agreements you have made about this world (which is in your mind) null and void.  And this changes the Mind.  And this changes your reality, your perception and your experience of this world. 

How it all happened (in theory) is that you as Sovereign Self, have chosen (through agreements) to experience life not as True Sovereign Self but as Ego Self.  Sovereign Self has given over the decision making Power to Itself AS EGO-SELF (Remember this is just a theory - a story). 

But, as the story goes, now, Sovereign Self, as EGO-Self, thru experience, gathers more memories, more desires, more fears, more joys, and more beliefs.  And more agreements are made and more emotional responses and more limitations are determined and agreed upon and so on.  Finding these agreements and revoking them goes a long way in changing for the better how we think, feel and perceive this experience we call Life on Earth.