"We must not fight fire with fire. We must not fight hate with hate," said Kaleka's son, Pradeep. "My father used to say that you can't put a fire out by pouring gasoline on it."
The attacker, Wade Michael Page, was a 40-year-old former soldier-turned-front man for a white supremacist rock band. He killed himself in the parking lot of the gurdwara after being shot by a police officer, the FBI said Wednesday.
Investigators say they found no clues to explain why Page went on the killing spree. Former Army colleagues said he espoused racist views during his military stint in the 1990s that became more pervasive after he left the service.
The incident occurred slightly more than two weeks after a shooting at a movie theater in Aurora, Colorado, left 12 people dead and 58 wounded.
Civil rights leader Jesse Jackson, who visited the gurdwara on Thursday, said more massacres will come unless the United States tightens up its gun laws.
"It's easy to be polite to say 'We're so sorry this happened' and give the same speech at the next killing a month from now," Jackson said, calling for a move from "politeness to a change in policy."
Jackson delivered the closing prayer at Friday's memorial service.
A CNN/ORC International poll released Thursday indicates that the public remains divided on gun laws, with 50% saying they favor no restrictions or only minor restrictions on firearm ownership and 48% supporting major restrictions or a complete ban by individuals except police and other authorized personnel.
Those numbers are identical to where they were in 2011, and the number who support major restrictions or a complete ban has remained in the 48%-to-50% range for more than a decade.
The CNN survey was conducted by ORC International on Tuesday and Wednesday, after the attack on the Sikh temple.
Also Thursday, temple members swept, scrubbed and painted over damage to their building when investigators allowed them back inside four days after the attack. A lone bullet hole remained in a metal door frame, which members say won't be repaired.