"Don't go to work Tuesday," Jackson exhorted the pastors and community organizers gathered to see him in the basement of the Greater New Hope Baptist church.
The 71-year-old urged people to take a sick day or a personal day off of work in order to convince people to get to the polls.
"Work all day long turning out the vote on Tuesday," he insisted. "Better to take sick leave for one day than to be really sick for eight years."
Dubbing election day 'Dignity Day', he talked of "special days in our lives", and brought up the Jewish baseball player Sandy Koufax who refused to pitch the 1965 World Series, because it fell on the Yom Kippur holiday.
"Every vote counts," he told the crowd, accusing the Republicans of trying to "steal" the election. "But the score is going to be so big they can't steal nothing," he said. "We're going to win this."
After his speech, he explained that groups attempting to intimidate voters, through challenges to their registration status, for example, are only making people want to vote more.
"The threats have inspired people rather than discouraged them. Voter suppression has turned into a stimulus. I think that people are awakened and aroused, who otherwise would have slept in. In many ways the voter purging and suppression schemes have backfired."
He said voter suppression attempts this year in Ohio were worse than he has ever seen - a strong statement from someone who was part of the American Civil Rights movement, and marched with Dr Martin Luther King, Jr.
"This is worse than it was in the South," he told RFI. "In the South it was just straight up black and white, you can't vote. Here you have this array of sophisticated schemes to undermine the vote. It's more sophisticated than it was in Alabama and Mississippi; not as pervasive, but more sophisticated."
Church leaders in Cincinnati are gearing up for a big get-out-the-vote effort on Sunday, as the early vote centre is open until 5pm.
Nelson Pierce, pastor of Cincinnati's Beloved Community Church and the lead organizer for the AMOS project, a federation of congregations, is asking people to go vote after church on Sunday.
He is organizing the Souls to the Polls operation that will gather people at churches and bring them to vote after services.
"What would it look like if God won Cincinnati?" he asked the crowd Saturday night.
He too asked people to take a day off to volunteer to get the vote out.