The interview will air about a week later on the Impact Network, Bishop Jackson’s Christian cable TV channel. The official said several Trump aides would work with the network to edit the taped interview so that the final version reflected the campaign’s wishes. (On Thursday night, Mr. Miller said the campaign would not edit the interview.)

The arrangements had angered several black Republicans, who urged Mr. Trump, widely seen as distant from the black community, to speak for at least 10 minutes at the service, the official involved in the planning said. The official added that the campaign had been uncomfortable with Mr. Trump’s speaking before the congregation and had insisted on a private interview.

On Thursday night, the campaign said Mr. Trump would indeed address the congregation for a few minutes and would spend a half-hour casually speaking with church members individually.

Mr. Trump is well known for veering from prepared remarks or throwing them away entirely. That could happen on Saturday: Many of the answers being prepared for him do not sound much like Mr. Trump as his usual self.

When asked about his vision for black Americans, the script suggests that Mr. Trump stay positive, advising that he use lines such as “If we are to make America great again, we must reduce, rather than highlight, issues of race in this country” and “I want to make race disappear as a factor in government and governance.”