On the horizon, there was the blocky spire that was the air traffic control tower. Every now and then a seagull would alight on one of the trailers where the cabbies play dominoes during their wait for fares. Occasionally, a silhouetted plane would glide by overhead, providing a rumbling accompaniment to the music.

But despite the setting  or maybe because of it  Mr. Quint’s audience seemed particularly moved by his gesture.

“I like that he came here,” Ebenezer Sarpeh, 46, said, in the accent of his native Ghana. “And, yeah, the music, I like it.”

It was Mr. Sarpeh who burst into spontaneous applause on several occasions and started yelling “magic fingers” during one particularly deft moment. Later, he took a turn in front of the stage and his fellow cabdrivers laughed and cheered while he shimmied and moonwalked, the Newark Taxi Cab Association’s answer to Justin Timberlake.

Like many of the cabdrivers in attendance, Mr. Sarpeh said it was the first recital by a classical violinist that he had ever attended. A few confessed that they had little more than a passing familiarity with such music. But they were proud to surround Mr. Khalil, who sat front row center in a black suit with a pink shirt and matching tie.

“If one cabby does something good, we feel like we all do something good,” said Patrick Cosmeus, 43, who has been driving for a decade and seemed a little sheepish as he admitted that he had seldom found anything more valuable than a forgotten cellphone in his taxi. “But everything we find, we always return it,” he added.

“Everything we find is valuable to someone,” Mr. Khalil pointed out. “If you lost your pen, you would think it was valuable.”