One thing that scared me and made me examine the church's leadership landscape was his discourse to the Ephesian elders in Acts 20. Within that discourse, he prophetically announces that wolves will come in to devour the flock, and "from among your own selves will arise men speaking twisted things to draw away the disciples after them" (v.30). Did you get that? From "your own selves." From the very elders that he is speaking to and encouraging and exhorting. From those that should be guarding the flock will come the wolves that seek to devour it. From those who should care for the doctrinal and moral purity of the church will come those that have neither kind of purity and will entice others away.
That's scary stuff and drives me to live out v.32 in my ministry: committing people to God and to the word of His grace. More Bible, less opinion. More Bible, less email. More Bible, less meetings. More Bible, less PowerPoint. You get the idea. Only the Scriptures can build others up and give an inheritance among those who are sanctified.
But that's just me thinking thoughts...