Eastertide   is   a   period   of   fifty   days,   which   runs   from Easter    Day     until    the    Day    of    Pentecost .        It    is    the Church's   season   celebrating   the   Resurrection   of   Jesus Christ.      It   actually   starts   in   the   evening   of   the   Saturday before Easter Sunday at the Vigil and First Mass. Jesus'    Resurrection    was    not    a    reversal    out    of    death.      Instead,   by   the   power   of   His   Sacrifice,   He   has,   as   it were,   blasted   through   the   dead   end   of   mortality,   opening a   path   from   this   life   to   reconciliation   and   reunion   with God.      During   Eastertide   we   contemplate   the   hope   that this Resurrection offers us. The   first   week   of   this   period   is   called   the   Easter   Octave   (=   a   period   of   eight   days),   which   is   an   intense   period   of celebration.  It ends on the Sunday after Easter Sunday; this latter Sunday is often called Low Sunday . The   Liturgy   reflects   this   hope   and   joy   in   various   ways   -   not   least   a   liberal   sprinkling   of   alleluias   attached   to the   end   of   the   various   texts   we   sing   and   say.      In   church,   the   principal   symbol   of   the   Resurrection   season   is the Paschal Candle , consecrated at the Easter Vigil and lit at every Liturgy during Eastertide. Forty   Days   into   Eastertide,   we   celebrate   Ascension   Day    when   we   recall   Christ's   return   to   sit   at   the   right hand of God: Jesus   led   the   Eleven   out   as   far   as   Bethany,   and   lifting   up   his   hands   he   blessed   them.      While   he   blessed   them, he parted from them, and was carried up into heaven. Luke 24: 50f see also Matt 28: 16ff Ten   days   later,   we   celebrate   the   Day   of   Pentecost .      This   recalls   the   events   recorded   in   the   Book   of   Acts   (2: 1   -   11)   when   the   Holy   Spirit   was   bestowed   on   the   Apostles   (see   also   John   20:   19   -   23).      We   traditionally understand this to mark the nexus between the incarnate Ministry of Jesus and the life of the earthly Church.