His boss 'assured' him that he had her continued support. = His boss 'assured' him of her continued support. = “You have my continued support,” his boss 'assured' him.
You can 'rest assured' [=you can be sure] that these mistakes won't happen again. = 'Rest assured', these mistakes won't happen again.
They are not 'assured of' being paid. [=it is not certain that they will be paid]
(..) in your neck with his damned fingers... ...force you to ravel all this matter out That I essentially am not in madness, but mad in craft Be thou assured, if words be made of breath and breath of life... ...I have no life to breathe what thou hast said to me Mother, goodnight (..)2015 Hamlet