AllSaints'Day(intheRomanCatholicChurchofficiallytheSolemnityofAllSaintsandalsocalledAllHallowsorHallowmas[1]),oftenshortenedtoAllSaints,isasolemnitycelebratedon1NovemberinWesternChristianity,andonthefirstSundayafterPentecostinEasternChristianity,inhonourofallthesaints,knownandunknown.
IntermsofWesternChristiantheology,thedaycommemoratesallthosewhohaveattainedthebeatificvisioninHeaven.ItisanationalholidayinmanyhistoricallyCatholiccountries.IntheRomanCatholicChurch,thenextday,AllSouls'Day,specificallycommemoratesthedepartedfaithfulwhohavenotyetbeenpurifiedandreachedheaven.
ChristiandenominationscelebratetheSolemnityofAllSaints'DayandtheFeastofAllSouls'Daybecauseofthefundamentalbeliefthatthereisaprayerfulspiritualcommunionbetweenthoseinthestateofgracewhohavediedandareeitherbeingpurifiedinpurgatoryorareinheaven(the'churchpenitent'andthe'churchtriumphant',respectively),andthe'churchmilitant'whoaretheliving.ThosewhohavediedandarewithGodwatchoverthosestillliving,andthesaintsareheldtointercedewithGodonbehalfoftheliving.Ontheirpart,thelivingpraytothesaintsandrememberinintercessoryprayerstoGodallwhohavedied,particularlytheirdeceasedrelativesandfriends.