Jernigan spent the previous two seasons in Philly after being acquired in an April 2017 trade with the Baltimore Ravens. Financial details of his new deal weren't immediately released.
The 26-year-old Florida State product missed most of the 2018 season while recovering from back surgery last May. He registered 29 total tackles and 2.5 sacks across 15 appearances for the Eagles in 2017.
In November, the Florida native said he was "nervous" about his football future after undergoing surgery, and that provided motivation when he returned.
"I will never let anybody play with more passion and purpose than I plan to play this game with as long as I'm playing," Jernigan told reporters. "It definitely means so much more to me. It's definitely been tough watching."
Jernigan tallied 91 total tackles and 13 sacks across three years with the Ravens, who selected him in the second round of the 2014 draft.
He'll provide depth at defensive tackle behind Fletcher Cox and Malik Jackson in 2019.