In his Pentecost 9 sermon Clay Nelson examines the difficulties in speaking truth to power.  How do we determine truth?  To whom do we speak it?

"It is a phrase that resonates for us.  It rings of courage and righteousness with more than a hint of danger.  I think it is why the politically satirical Daily Show with Jon Stewart who does this nightly, is a global phenomenon.  Few of us would be displeased to have it said of us at our funeral… “She or he spoke truth to power.”  Yes, that sounds like high praise..." 

Full text with video links at http://www.stmatthews.org.nz/nav.php?sid=503&id=953.