Be Still and Know That I Am God - What Does it Really Mean?

For as long as I can remember I've heard this verse cited with the encouragement that God is telling us to be still and make ourselves aware of who he really is.  In that time of "stillness" we will experience God in ways that could not be done apart from being still.  I came across this again in something I read recently so I thought I would look up what John Goldingay had to say in his commentary on the Psalms in the Baker Commentary on the Old Testament Wisdom and Psalms.  I found part of it surprising and part of it alarming. I put in italics what surprised me and in bold what alarmed me. 

"'Be still and know that I am God' is a common invitation in Christian spirituality.  This involves a reinterpretation of the psalm.  Nowhere do the psalms have an ideal of silence.  Their assumption is that one finds God not in silence but in noise.  In noisy Western cultures, we may need to cultivate silence, and the use of the psalm to this end may be inspired by the Holy Spirit, even though it does make the words mean something that the psalmist did not say and would not have dreamed of saying.  Spirit-inspired interpretation often works by making the words of Scripture mean something quite different from what they actually meant, because new situations make it necessary for God to say new things.  At the same time, we have to be wary of missing what the text actually did say.  Here it issues an important challenge to the superpower to stand still and recognize that God is God and that the superpower is not."  (vol. 2, p. 73)

I was surprised, though not terribly so, to see that the verse taken from its context had acquired a life of its own and had taken on meanings not found in the text.  But then Goldingay goes on to offer a justification for this very practice.  As it turns out "spirit-inspired interpretation" can make "the words of Scripture mean something quite different from what they actually meant."  Now he is not writing a book on hermeneutics so I understand him not going into much detail on this point but this seems to open a pandora's box for subjective interpretations under the guise of "spirit-inspired interpretation."  I appreciate his caution that we should "be wary of missing what the text actually did say" but couldn't some one say "What does it matter what it originally said since I have a spirit-inspired interpretation that is not confined to the original meaning?"  At the end of the day what is there to be wary of?  I suppose if you're trying to say what it originally meant then the caution is applicable but with that out of the way the door is open to just about any thing that fits my fancy since a new situation may be making it necessary for God to say something new.