Teacher, shepherd, both, or neither?

What role do clergy play in modern religion? Obviously the answer varies based on many specifics, but what's the ideal? Are they there to help us find our way, to help us learn about religion, to be a teacher, a rabbi? Are they there to lead us to the right path, to ensure that we find God, to be our pastor? Is it the mission of these individuals to inspire us, to be sure we follow tradition and/or ritual, or are they simply a resource we have at our disposal but need not follow explicitly? Are they necessary, sufficient, or helpful in reaching spirituality or unifying a religious community?