As a first cut, I am looking for a church that would have invited Martin Luther King to speak to the congregation, or at least had a clear understanding why they would not have chosen to do so.
As a contrast, consider some other general church types in America today. The first I shall call "the shallow church." They sing some hymns and preach a homily. People are attracted to the fellowship, choir rehearsals and potlucks. They have some good projects, but for them Christianity is only an add-on, certainly not something that would incite members to fight for radical change.
Then there is "the misled church" that puts its money where its mouth is, but its mouth is in the wrong place. In the name of "fairness" and "inclusivity," they advocate things like "marriage equality" and thereby replace biblical truth with their warped feelings of fairness. Some carry the banner of "Black Lives Matter" and beat the drum that all racial disparities are caused by current white racism. Or how about organizing members to oppose Trump just because he is Trump? Let's focus hatred on Trump with signs proclaiming, "Love Trumps Hate."
Then we have "the campus church," which helps people to be more like Jesus. However, as people don't want to be treated the way Jesus was treated, this church tends to help their members be only like that portion of Jesus that does not lead to the downside of being like him. They encourage members to personal piety – Bible study and prayer as well as good works. These churches may even preach biblical truths that are offensive to our culture – but don't worry, they are only preaching to themselves. While they may be greatly concerned about what their kids are exposed to, they draw a line around those they are closest to and write off what happens outside the circle. They keep their beliefs on campus.
Their model for transforming the culture is to make more Christians like themselves, but they fail to realize that if a hundred inert Christians grow to 10,000 inert Christians, the results will be the same. Does your city have an annual festival that celebrates perverse sexual sin? Better not to talk about it or try to impose our values on them as they have on us.
Then we have "the pivotal church," the one that would have invited MLK to speak. MLK embraced the other half of Christ. He was oblivious to what people thought of him and was unafraid to ask followers to do things that got them beaten, jailed and killed, and endured the same himself. MLK did not politely ask for change. Rather he demanded it. He turned the standard church model on its head. Normally, a pastor spends his time building up his church and ignores those outside or deliberately limits its sphere of influence. MLK sought to have those in the church pour out their lives for the benefit of nameless masses, and he transformed the culture.
When a church says, "I don't care what it costs. I don't care what you say about me. I don't care what you do to me. I'm not going to let you trash my city," that church will transform the nation.
I'm not suggesting the pivotal church would have wanted MLK as a pastor, because he wasn't one. Rather he was an evangelist for what should have been a Christian value, racial equality. Such a pivotal church that pursues unpopular Christianity while adhering to biblical truth will transform a city.
I live in West Seattle. Let me know what you find.