It may seem strange to describe Holy Saturday as “The big day”. In terms of salvation the Crucifixion on Good Friday and the Resurrection of Easter would seem bigger. Yet in terms of the church the biggest mass of the year comes on Holy Saturday in the form of the Easter Vigil.
You have the Mass beginning with a ceremony of fire, more scripture readings than any other mass of the year (even the abbreviated mass has five or more ) the return of the Alleluia and the reception of converts into the church, a veritable salmagundi of devotions and prayers.
Why have all of this at the vigil rather than at Easter, because it is at the end of that fateful Saturday when everybody from the Chief Priests to the Romans to even the disciples thought that Jesus and his ministry were finally at an end. None of them suspecting that Christ, having conquered sin, was about to conquer death and change the history of humanity forever.
It would not be until the next day that the women would find the stone rolled away, the tomb empty, the guard nowhere to be seen. It would not be until the next morning that the Jewish authorities would find themselves confounded indeed it would not be until many weeks that the disciples who fled would become the martyrs unafraid of death.
The disciples, the Romans (with the exception of the guards) and the Jewish Authorities had no idea what was brewing that night and coming with the dawn of the new day but two thousand years later we do!
If that’s not worth a long mass I don’t know what is.