Donald J. Trump’s civil fraud trial enters its final phase on Thursday as each side presents closing arguments in a case that has enraged the former president and threatens his family business.

Lawyers for the New York attorney general, who sued Mr. Trump in 2022, will argue that the former president violated laws when he fraudulently exaggerated his net worth to obtain favorable loans. The accusation strikes at the heart of Mr. Trump’s presentation of himself as a real estate visionary and has made the attorney general, Letitia James, one of his chief antagonists.

Ms. James’s lawyers will highlight evidence from the monthslong trial, including internal emails and the testimony of onetime Trump employees, asserting that Mr. Trump’s actions warrant a severe punishment. Ms. James wants to extract a $370 million penalty, and to oust Mr. Trump from his own company and the wider world of New York real estate.

Mr. Trump’s lawyers will offer a competing narrative: that Ms. James fell woefully short of showing that the former president had orchestrated fraud in his annual financial statements and that the statements themselves were essentially irrelevant to the loans he received. They will most likely point to the testimony of Mr. Trump’s bankers, who extolled the former president as a reliable borrower.

“No bank or underwriter was, or would have been, materially misled by the alleged misstatements,” defense lawyers wrote in legal papers, noting that current and former Deutsche Bank employees had testified that the bank did its own “extensive due diligence” on Mr. Trump’s net worth.

While Mr. Trump had hoped to speak in his own defense on Thursday, the judge overseeing the case, Arthur F. Engoron, imposed limits on his remarks. Justice Engoron ruled that the former president could not deliver “a campaign speech” or attack the judge, his staff or Ms. James.