Elvis Presley always told people that his identical twin brother Jesse, who died at birth, was with him throughout his life.
Ray says his first time meeting Axel was in the vents of the Waverider during the events of Turncoat (2017), and subsequent giving him to Mick as a Christmas present.
During the dance in the church some couples are doing the "Twist", which was still a few years away in 1954, the year when the aberration took place that resulted in Memphis becoming a ghost town.
The title of the episode is a nod to the hymn of the same name, which Elvis sings to put the dead to rest.
Nate tells everyone to "shake, rattle and roll" while they go to replace Elvis' guitar, referencing Elvis' covers of the same name.