This is both the good news and the bad news. While it is scary to think that God works through weak, partial, and limited mortals like us, the only thing scarier would be thinking that he doesn't.
It's a false dilemma to claim that either God works through flawless people or God doesn't work at all. The gospel isn't a celebration of God's power to work with flawless people. The gospel is a celebration of God's willingness to work today, in our world, in our lives, with people who clearly aren't. To demand that church leaders, past or present, show us only a mask of angelic pseudo-perfection is to deny the gospel's most basic claim: that God's grace works through our weakness. We need prophets, not idols. Our prophets and leaders will not turn out to be who you want them to be. They are not, in fact, even what God might want them to be. But they are real and God really can, nonetheless, work through their imperfections to extend his perfect love.
Our church manuals and church histories are sometimes shy about this good news. With good intentions, they worry over your faith. Sometimes they seem too much like that friend of a friend who really just wants you to like them, and so they pretend to only like the same things they think you do. But God is stronger stuff than this. And the scriptures certainly are as well. If, as the bible makes clear, God can work through liars, thieves, adulterers, murderers, prostitutes, tax collectors, and beggars, he can certainly work around (or even through) Joseph Smith's clandestine practice of polygamy, Brigham Young's strong-armed experiments in theocracy, or George Albert Smith's mental illness.
In the parable of the mustard seed, Jesus innocently compared the kingdom of God to "a mustard seed that someone took and sowed in the garden; it grew and became a tree; and the birds of the air made nests in its branches" (Luke 13:19 NRSV). This is a nice story, but we've forgotten about mustard seeds. It would have been plain to Jesus' audience that this parable was meant to vex them. People have big ideas about what the kingdom of God is supposed to be like, but teeny tiny mustard seeds like Jesus described don't grow into towering cedars. Generally, they don't amount to much more then overgrown bushes. More, Jesus' audience would have known that mustard plants aren't typically grown in gardens. When growing a garden, you're more likely to spend your time weeding them out. Rather than being a cash crop, mustard plants are more like stubborn weeds liable to hijack your whole plot. Jesus means this parable as a kind of warning. Don't expect, Jesus says, the kingdom of God to look like a massive oak tree. Expect it to be more like a weed that, without your quite intending it, overruns your garden and crowds out the stories you'd been hoping to tell.
At some point, God will ask you to sacrifice on his alter not only your stories about your own life but your versions of his stories as well. Your softly lit watercolor felt-board versions of scripture stories and church history must, like all the stories, be abandoned at his feet, and the messy, vibrant, and inconvenient truths that characterize God's real work with real people will have to take center stage. If they don't, then how will God's work in your hungry, messy, and inconvenient life ever do the same?
When God knocks, don't creep up to the door and look through the peephole to see if he looks like you thought he would. Rush to the door and throw it open.