Pictured: Good Friday at MSH, 2009
Good Friday was a special day of prayer from the earliest days of Christianity. The structure of the liturgy celebrated that day can be traced back as early as the fourth century: A three-hour service of Scripture readings (including the Passion according the John), psalms and prayers. The celebration of the Mass was not allowed. Seventh-century records indicate that the faithful did receive holy Communion from what had been consecrated on Holy Thursday (that is why this liturgy later came to be called the Mass of the Pre-Sanctified).
Because in later centuries fasting from midnight was required in order to receive Communion, Good Friday service was later moved from the afternoon to early morning. By the Middle Ages, only the priest was allowed to receive Communion. Many Catholics will still remember this liturgy: Black vestments, a wooden clapper, clergy and servers removing their shoes to venerate the cross (which they still do!).
In the 17th century, a devotional afternoon Good Friday service developed called "Tre Ore" ("Three Hours," from noon to 3:00PM). The morning liturgy was still celebrated, but most people came to the afternoon prayer service. Since it was a devotion, the structure of the service varied from parish to parish. Generally it included a sermon, the Stations of the Cross, hymns and prayers. Many people did not stay for the whole three hours, but came and went as they were able.
In the 1955 reform of the Triduum, the morning of God Friday liturgy was revised and moved again to the afternoon, replacing the Tre Ore services.