It is a day on which the Jewish Council made a consultation to crucify the Lord on Friday. (Jn. 11:46-53). Instruction is given that Christians should fast on this day always remembering the sentence of death made against Christ, the Savior of the World, who died for the sake of mankind.
As is well Known, Friday is a blessed day on which the Lord was crucified in his flesh and the hope of redemption which was expected for a long time was fulfilled. (Jn. 19:17-30; Lk. 23:26-49). Thus it is canonized that except during the fifty days after Easter and during the feasts of Christmas and Epiphany when these feasts fall on these days, Wednesdays and Fridays should be observed every week in fasting and prayer. (The Law of Kings article 15; Didas. 29).