Some experiences affect us so powerfully that we never forget them.  The awe, terror, and even beauty of those moments stay with us the rest of our lives.  Negatively, I think of 9/11 and the recent Capitol riot.  Positively, I think of my wedding day and the birth of my first child.  

The prophet Isaiah had an experience that trumps all of those -- a vision of the holy and transcendent God, the King of the universe.  It shook him to his core, but also propelled his call to ministry.  He tries to describe the indescribable, a vision of the Holy One that changed him forever.  

He volunteers for God's service, but things don't go as planned.  Rather than his words causing people to repent and turn from their evil ways, they seemed to have the opposite effect -- people became even more entrenched in their sin and stubbornness.  Even Jesus and Paul experienced this heartbreaking, haunting irony in their ministries, their very words seeming to "make the heart of this people calloused; make their ears dull and close their eyes." (Isaiah 6:10)

We would do well here to consider the stern warning about the subtle, hardening effect of sin in our lives, the power it wields to exert a kind of spiritual momentum over us to increasingly close us off to God's love and truth.