Mr. Biden, a Catholic, described his faith as the “bedrock foundation of my life” that sustained him after he lost his first wife and daughter in a car accident, and later, his adult son Beau Biden to cancer.
“For President Trump to attack my faith is shameful,” Mr. Biden said, calling it “beneath the office he holds.” He added that the attacks “show us a man willing to stoop to any low for political gain, and someone whose actions are completely at odds with the values and teachings that he professes to believe in.”
Mr. Trump maintained that Mr. Biden frequently is confused about his whereabouts, during a speech in which the president mispronounced Thailand as “Thighland,” catching himself a short time later.
The president spoke as his aides struggled to get a deal for new legislation to help people suffering economic pain caused by the coronavirus, something Mark Meadows, his chief of staff, and Steven Mnuchin, the Treasury secretary, have been scrambling to achieve in negotiations with Democratic leaders. Mr. Trump has not been a meaningful part of the talks, preferring to comment from the sidelines. After a fund-raiser on Thursday evening in Ohio, he will head to his private club in New Jersey and has fund-raisers scheduled this weekend.
Mr. Trump’s swing through Ohio took him to Clyde, where he toured a Whirlpool factory. The president wore a mask as he walked through the plant, giving a thumbs-up sign to photographers nearby, a notable move given his longstanding resistance to the masks until the past few weeks. Mr. DeWine has been a proponent of masks; he issued a statewide order requiring them last month.
Then, standing at a lectern with the presidential seal, his face glistening with sweat, Mr. Trump delivered a winding series of remarks that were ostensibly about trade and the economy, but that took several detours into criticizing Mr. Biden and complaining about his political lot in life.
“I had such a beautiful life before I did this,” Mr. Trump said at one point.
The president’s inability to stick to his script has infuriated and exasperated his advisers, who believe he could be in a much stronger position in the campaign if only he would stop creating so much content for his critics and opponent.