Comey said they were talking about jihad and martyrdom before they became engaged and started living together, which means they were radicalized as early as the end of 2013. The couple wed last year.
U.S. officials previously said that Farook, a U.S. citizen originally from Chicago, traveled to Saudi Arabia in July 2014 and returned less than two weeks later with Malik in tow. Malik arrived in the U.S. on a Pakistani passport and a fiancee visa.
Comey said the couple was inspired by foreign terror organizations.
"We're working very hard to understand exactly their association and the source of their inspiration," Comey said. "We're also working very hard to understand whether there was anybody else involved with assisting them, with supporting them, with equipping them. And we're working very, very hard to understand, did they have other plans? Either for that day or earlier, and that work continues."
Eyewitness News has learned of indications that Farook had been plotting an attack with someone else in 2012, but got spooked after a round of terror-related arrests.
ABC News reports that members of Congress were informed by the FBI that Farook's former neighbor, Enrique Marquez, is believed to be the accomplice in that 2012 plot, the news source said.
Malik's father, Gulzar Ahmad Malik, said Wednesday that he condemns and regrets his daughter's actions.
"I am in such pain that I cannot even describe it," he said. "Whatever God does only he knows better, and only God knows why did it happen."
Wednesday marks one week since the deadly terror attack at Inland Regional Center in San Bernardino that left 14 people dead and 21 others injured.
MORE: Here are the faces of those killed in the San Bernardino shooting
Two ceremonies were scheduled Wednesday to honor those who lost their lives at the hands of Farook and Malik.
A moment of silence was held at San Bernardino Valley College at 11 a.m, and a vigil is scheduled to be held at Water of Life Community Church in Fontana at 5:30 p.m.
Meanwhile, Farook's mother has been placed on the FBI's terrorist watch list. His 66-year-old father was placed on that list two days ago. Authorities say this is a precautionary measure to make sure Farook's parents don't leave the country.
MORE: What we know about the San Bernardino mass shooting
Federal investigators are also trying to determine a money trail for funding of the San Bernardino mass shooting. About $28,000 was deposited into Farook's account shortly before he and his wife carried out the attack on Dec. 2. The money could have possibly come from an online lending company, authorities said.
Eyewitness News learned that Marquez married the sister of Syed Farook's brother's wife, but there is little evidence they acted like a couple, and investigators are taking a close look at the marriage.
This comes after news that the 24-year-old may face criminal gun charges after federal authorities said Marquez may have purchased two of the weapons used in the attack because Farook didn't want his name on file in connection with the assault-style rifles.
Friends say Marquez may have known about the terror plot in advance. He has since checked himself into a mental facility.
Two buildings at the Inland Regional Center will remain shut down until 2016. Building 3, which is where the mass shooting took place, has been closed indefinitely.