The service was explained by Haydn himself in an introduction to the composition of his work on the Seven Last Words:
Some fifteen years ago I was requested by a canon of Cádiz to compose instrumental music on the seven last words of Our Savior on the Cross. It was customary at the Cathedral of Cádiz to produce an oratorio every year during Lent, the effect of the performance being not a little enhanced by the following circumstances. The walls, windows, and pillars of the church were hung with black cloth, and only one large lamp hanging from the center of the roof broke the solemn darkness. At midday, the doors were closed and the ceremony began. After a short service the bishop ascended the pulpit, pronounced the first of the seven words (or sentences) and delivered a discourse thereon. This ended, he left the pulpit and fell to his knees before the altar. The interval was filled by music. The bishop then in like manner pronounced the second word, then the third, and so on, the orchestra following on the conclusion of each discourse. My composition was subject to these conditions, and it was no easy task to compose seven adagios lasting ten minutes each, and to succeed one another without fatiguing the listeners; indeed, I found it quite impossible to confine myself to the appointed limits.
These services were very common in the past but after Vatican II because of the change of time to the evening for the Good Friday Service, the practice of the Seven Last Words disappeared, for the most part. You do have it in convents and monasteries and also in certain parishes but no longer has the prominence as in the past. Having the service on Saturday morning was very appropriate and makes the building up to the last three days with the Seven Last Words a fitting preamble to the Climax at the Easter Saturday Vigil Mass.
Surfing to see what was listed under Seven Last Words in Korean I was surprised to see so many Protestant Churches having the service.One of the most beautiful meditations that I have read on the 7 last words was by a Protestant minister. You also see some ministers recommending the rosary to their congregations. The praying modes of the different Christian Communities should be something that we should be able to accept. The Protestant musical tradition has entered the Catholic Church, and the Protestants are being attracted to many of the Catholic prayer forms. This should be a help in understanding each other with fewer misunderstandings, and giving us a common desire to be closer in discipleship to Jesus.