In the course of the ninth century the cult of the relics of the saintly sisters became increasingly important and included the veneration of the Codex Eyckensis, which inspired deep reverence as a work produced by Harlindis and Relindis themselves.
U toku devetog stoljeća zaostavština svetih sestara postaje sve važnija a uključuje i štovanje knjige Codex Eyckensis, koja je budila duboko poštovanje kao djela kojeg su stvorile same Harlindis i Relindis.