He was 47 and lived in Freeport.
Burnett was a longtime community leader who was best known for helping others.
"He was a big man with a bigger heart, and I loved and respected him," said Hempstead Village Trustee Perry Pettus.
Former Mayor Jim Garner, now a deputy county comptroller, said back in 1994, when "five children died in a village fire, Gerard stepped up to help big-time."
Nassau County Court Judge Jerald Carter called Burnett "The biggest, gentlest, kindest person I've ever known."
Burnett graduated from Uniondale High School in 1981, then C.W. Post at Long Island University in Brookville in 1985, with a bachelor's of science in management and marketing. While on campus, he was a member of the Student Government Association and the track and football teams.
He joined the Kappa Rho chapter of the Alpha Phi Alpha fraternity.
The following year he graduated from the American Academy McAllister Institute of Mortuary Science (now of Funeral Services) in Manhattan.
In 1989, Burnett's father, Carl C. Burnett, who started the Hempstead funeral home in 1973 with his wife, Thelma, died, and his son took over its management.
"I probably should not have put that much responsibility on him so soon, but he handled it well," said his mother.
She said her son always seemed drawn to the church and to giving to others.
"He joined the Presbyterian Church in Hempstead when he was 3 and remained there until he graduated from college," she said, adding that he got his first teaching assignment in its Sunday school.
After college, Burnett joined Antioch, now led by the Rev. Dr. Phillip E. Elliott, a Nassau deputy county executive.
"As good a leader as he [Burnett] was in the community and business, he was just as good a student, a learner, in religion," said Elliott, who made him a minister in 2009.
Just last month, Burnett earned his master's of divinity from the New York Theological Seminary in Manhattan.
Burnett married Regina Stevens of Hempstead in 1996, and they have a son, Gerard Jr.
Among the many associations he belonged to was 100 Black Men of Long Island, and Operation Get Ahead in Hempstead. He was three-term president of the Empire (State) Funeral Directors.
A service will be held at 11 a.m. Friday at Union Baptist Church, with burial to follow at Greenfield Cemetery in Uniondale.