Numbers 35:25

and the congregation shall deliver the slayer out of the hand of the revenger of blood, save his life by preventing his execution by the hand of the revenger, and the congregation shall restore him to the city of his refuge, grant him safe-conduct to this haven of safety, whither he was fled, for the trial, of course, took place in his own city; and he shall abide in it unto the death of the high priest which was anointed with the holy oil, the incumbent of the office at the time of the trial. The death of the high priest thus released him from his banishment.