1
general::
Don't worry that a thing will or won't occur, be confident, as in I'll get there, never fear. This phrase was used by Christopher Marlowe in Doctor Faustus (c. 1590): "‘Tis but a surfeit; never fear, man."
American Heritage Idioms
2
general::
Phrase(s): never fear
do not worry; have confidence. • I’ll be there on time—never fear. • I’ll help you, never fear.
McGrawhill's American Idioms And Phrasal Verbs