This is an event to remove committed sins and stains, and Oharae held in June and Oharae held in December are called Nagoshi no Oharae (great purification ceremony) and Toshikoshi no harae (Annual Shinto ritual of purification), respectively.
犯した罪や穢れを除き去るための祓えの行事で、6月の大祓を夏越の祓（なごしのはらえ）、12月の大祓を年越の祓（としこしのはらえ）という。