Rest Assured 

A phrase that is utilized to express positiveness, a guarantee, or just general "knowing" of a person, subject, or event.

Jake: "Was the party at TJ's really as cool as everyone said it was?"
Dre: "Hell yeah man. Everyone was having a good time."
Jake: "Man, for real? And I missed it?!"
Dre: "Rest Assured Jake. You missed more than you'll ever know..."

Rest Assured by stunna3098 October 9, 2011

restassured 

To be absolutely sure and confident in one's self and one's beliefs as to not care what anyone else might think.

He was too restassured to pay their insults any mind.

restassured by xrestassuredx November 23, 2006