“We must hold this president accountable for his stunning abuse of power,” Mr. Jeffries said as the House Judiciary Committee debated the articles of impeachment. “We must hold this president accountable for undermining America’s national security. We must impeach this president.”

Mr. Jeffries has shown few signs of tempering that approach. When a reporter on Tuesday asked him about comments made by Representative Kevin McCarthy of California, the Republican leader, suggesting former Vice President Joseph R. Biden Jr. should suspend his presidential campaign during the Senate trial, Mr. Jeffries deadpanned, “Who?”

“We will not take political advice from Kevin McCarthy,” he replied icily.

As likely to quote from the Bible as he is from 1990s hip-hop lyrics, Mr. Jeffries’s rhetorical skills were honed as a high-powered litigator working at an elite corporate law firm in New York, where he defended CBS in a lawsuit over Janet Jackson’s wardrobe malfunction at the 2004 Super Bowl.

Mr. Jeffries won his first race in 2006, securing a seat in the New York State Assembly after two unsuccessful attempts. He was elected to Congress in 2012.