WESTHAMPTON BEACH, N.Y. — When Jeb Bush stopped by the Hampton Synagogue here on Saturday, he was expected to offer a critique of the Iran deal and a short version of his stump speech to the Orthodox congregation.

But something else was on his mind: the insults hurled at him by Donald J. Trump.

“I’ll just give you a little taste of the ‘low energy’ candidate’s life this week,” Mr. Bush said, referring to the stinging taunt Mr. Trump has repeatedly used to describe him.

Mr. Bush then spent a minute and a half reeling off the cities he had visited since Monday — among them McAllen, Tex.; Salt Lake City; Denver; Pensacola, Fla.; Birmingham, Ala.; Greensboro, N.C. — and noted that, earlier in the week, he had risen at 6 a.m. to go running with former members of the Navy SEALs near the Virginia coast.

“The ‘low energy’ candidate this week has only been six days, 16 hours a day campaigning with joy in my heart,” he said.