A.T. Robertson Commentary Luke 21:17

"And ye shall be hated of all men for my name`s sake." — Luke 21:17 (ASV)

Not a hair of your head shall perish (θριξ εκ της κεφαλης υμων ου μη απολητα). Only in Luke. Second aorist middle subjunctive of απολλυμ with ου μη (double negative). Jesus has just said that some they will put to death. Hence it is spiritual safety here promised such as Paul claimed about death in Php 1:21.