Sarah Sanders, White House press secretary, told a religious television station that God wants "to become the presidency of Donald Trump."
Ms. Sanders argued in an interview with the Christian Broadcasting Network (CBN) that Mr. Trump was in office.
The press spokesman also said it was "very difficult" to take moral education from the Democratic Party.
The Democrats have attacked Mr. Trump's proposed border wall as immoral.
The US evangelicals strongly support the president.
The Washington Post reports that Trump won 80% of the Gospel vote in 201
- Trump's unlikely Christian Covenant
CBN aired Wednesday's interview with Ms. Sanders, led by David Brody and Jennifer Wishon.
Following Mr Brady's question about Mr Trump's position, Mrs Sanders said: 'I think God is calling us all to fill different roles at different times, and I believe he wanted Donald Trump to become President . "
" That's why he's here and I think he has done a tremendous job in supporting many of the things people of faith really care about. "
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Asked about House Speaker Nancy Pelosi's position on the proposed boundary wall – a bone of contention at the heart of the US government's longest standstill in history – the press spokeswoman attacked Ms. Pelose's suggestion that such a barrier was immoral.
"Honestly, at this point in time, it's very hard to give a talk by Democrats about what is and is not moral," she said. She called it a "ridiculous charge" and said that Ms. Pelosi "might even regret doing so".
"Protecting your country's population … is the fundamental duty of being President of the United States," said Ms. Sanders.
The interview comes a few days after Mr. Trump tweeted his Bible study support.
Several states have legislation that incorporates Bible courses into public education.
The American Civil Liberties Union attacked Mr. Trump.
"Mostly Bible studies in public schools are similar to Sunday classes, violating the rights of students and the rights of the first change of parents," wrote senior lawyer Heather Weaver.
"Public schools serve education, not religious indoctrination."