Lamor Whitehead, a Brooklyn preacher known as the “bling bishop” for his flashy luxury possessions, was convicted in Manhattan federal court on Monday of defrauding a parishioner and trying to extort a businessman while boasting about his ties to Mayor Eric Adams.

Mr. Whitehead, 45, was pronounced guilty on five counts, including wire fraud, attempted extortion and lying to the F.B.I. Prosecutors said that Mr. Whitehead, who had a previous conviction for identity theft, had lied and threatened to force his victims to give him money, and had misrepresented his relationship with the mayor.

“He was lying about the access, he was lying about the influence, he was lying about all of it,” Derek Wikstrom, a prosecutor, said in his closing argument.

The government said that Mr. Whitehead had persuaded the parishioner, Pauline Anderson, to invest about $90,000 of her retirement savings with him — and had then spent the money on car payments and goods from Louis Vuitton and Foot Locker. Other charges relate to his interactions with Brandon Belmonte, who was running an auto body shop in the Bronx. Mr. Whitehead tried to force Mr. Belmonte to lend him $500,000, while promising access to Mr. Adams, prosecutors said.

In the defense’s closing arguments, Declan Murray, one of Mr. Whitehead’s lawyers, likened criminal trials to the process of buying a house. He charged that the government’s case — the house, in this analogy — was poorly constructed and ridden with termites.

But the jury was not swayed by the defense.

Mr. Whitehead’s sentencing is set for July 1. He could face decades in prison.

Mr. Whitehead had considered Mr. Adams, 63, a former Brooklyn borough president, a mentor. The younger man sought to follow in his footsteps, launching a bid to become Brooklyn borough president in 2021. But Mr. Adams would not endorse Mr. Whitehead — and even admonished him for using his name in a “misleading” campaign ad, according to text messages prosecutors showed during the trial.

Mr. Murray shot back that Mr. Whitehead had only said that he could get a meeting with Mr. Adams “faster than most people” — and that statement, he contended, was true. But prosecutors also showed other messages from Mr. Whitehead to Mr. Adams in early 2022 that went unanswered.

That was an eventful year for Mr. Whitehead. In May, he was in the news when he reportedly tried to negotiate the surrender of a man who had fatally shot a Goldman Sachs employee on a Q train in broad daylight.

In July, three masked gunmen robbed Mr. Whitehead and his wife of expensive jewelry during a service at his church, Leaders of Tomorrow International Ministries, which was above a Haitian restaurant in Canarsie, Brooklyn. The service was being livestreamed, and the video made news around the country.

Then in December, he was arrested. The U.S. attorney for the Southern District of New York said at the time that the case was being investigated by the office’s public corruption unit.

A superseding indictment in 2023 added a charge stemming from a $250,000 loan that Mr. Whitehead took out for his business, Anointing Management Services LLC. Prosecutors said he had falsified bank documents for the application, claiming the business had $6 million in annual revenue. The indictment said that Mr. Whitehead had also used falsified bank statements to purchase his spacious home in Paramus, N.J.

“The numbers were made up,” Mr. Wikstrom said.