"I am sure some of you are sick and tired of politicians who just show up at election time... you and your congregations deserve more," Clinton said at the National Baptist Convention in Kansas City, Mo. this evening.
"Across this great country, you've welcomed me into your congregations with open arms and open hearts," she said.
"If he doesn't respect all Americans, how can he serve all Americans?" she said of Trump.
"You know better than anyone that people who look at the African American community and see only poverty, crime, and despair are missing so much," she said in an earlier veiled reference.
Before the conventions, Clinton received support from 89 percent of registered black voters who were polled about a two-way race; Trump got only 4 percent.
After the conventions, that gap widened, with Clinton receiving 92 percent of black support and Trump receiving only 2 percent.
Dr. Jerry Young, the president of the National Baptist Convention, also took a veiled dig at Trump, during his introduction.
"What is encouraging to me is her being here is not breaking news. And I am absolutely totally thankfully for that matter," he said.
During the remarks -- the first in four "Stronger Together" speeches she will deliver this month -- Clinton also opened up about her Methodist faith.
"Today for a few minutes, I want to leave aside the politics and do something that doesn’t always come naturally to a Midwestern Methodist. That is to talk about my own faith, how it led me to a life of service, how it will guide me as president," she said.
Clinton recalled how sometimes people ask her, "Are you a praying person?"
"And I tell them, 'If I wasn't one before, whew, one week living in the White House or on the campaign trail would’ve turned me into a praying person," she exclaimed.
"But," she added, "I had the great blessing of being raised by a family and church that instilled in me a deep and abiding Christian faith and practice."