This is going to be off the top of my head, so I hope I don't ramble into unintelligibility. And while the timing of this is related to Harold Camping's most recent prophecy failure, these thoughts have been developing in my mind for 30 and more years.
Just stating what Christian ministry and leadership is should inspire reverent (and sometimes, abject) fear, and be more than a bit intimidating. God is fully good, knows all and God's power is limited by God and nothing else. The very best human is flawed, not fully good and limited in knowledge and power. The flawed, limited, human being who ministers or leads, in that capacity represents and acts for God. And God chose to work through such flawed, limited, human beings!
Thus, Christian leaders and Christians who minister need to remember who they are. They need to remember - constantly - their utter insufficiency for what they are doing. Christian leaders need to rely on God to give them the power to do what they do, whether pastoring a church, leading a teaching ministry, leading a ministry that helps the needy, or cleaning the bathrooms of the church building. And such Christian leaders need to rely on God, not their own skills, for the fruit of their ministry. Ultimately, it is God working through the one who ministers and bringing results. In other words, while those who minister represent God in what they do, there is absolutely no room for pride or independence. Many Christian leaders who go astray do so stumbling into the traps of pride and/or independence. My guess - I could be wrong - is that Harold Camping fell into one or both of those traps 2 or 3 or 4 decades ago, and his false prophecies are just the most recent and visible expressions of a much older and deeper problem in his soul.