There's an "eternally significant" question Donald Trump and Joe Biden should ask themselves as votes continue to be counted, says John Piper, but it's not whether they've won this election. 

"The eternally significant question for Trump and Biden today is not, 'Was I elected?' But am I among God's elect," the Baptist pastor wrote.

He then suggested that Trump and Biden could confirm this "by humbly and joyfully exulting in Jesus Christ as their Savior and as their supreme Treasure." 

Piper divided Christian opinion in the run-up to election day on Tuesday when he wrote a blog on his Desiring God website making clear that he did not think Trump was fit for office. 

The theologian said that although anyone could be forgiven for their sins in Christ, but he remained "baffled that so many Christians consider the sins of unrepentant sexual immorality (porneia), unrepentant boastfulness (alazoneia), unrepentant vulgarity (aischrologia), unrepentant factiousness (dichostasiai), and the like, to be only toxic for our nation, while policies that endorse baby-killing, sex-switching, freedom-limiting, and socialistic overreach are viewed as deadly." 

"It is not a small thing to treat lightly a pattern of public behaviors that lead to death," he said.

"In fact, I think it is a drastic mistake to think that the deadly influences of a leader come only through his policies and not also through his person.

"Flagrant boastfulness, vulgarity, and factiousness are not only self-incriminating; they are nation-corrupting."