Analysis of information sources in references of the Wikipedia article "Sabbath in seventh-day churches" in English language version.
But while many God-fearing Christians were gradually led to regard Sunday as possessing a degree of sacredness, they still held the true Sabbath as the holy of the Lord and observed it in obedience to the fourth commandment.
{{cite book}}: ISBN / Date incompatibility (help)[self-published source]Let us therefore no longer keep the Sabbath after the Jewish manner, and rejoice in days of idleness .... But let every one of you keep the Sabbath after a spiritual manner, rejoicing in meditation on the law, not in relaxation of the body, admiring the workmanship of God, and not eating things prepared the day before, nor using lukewarm drinks, and walking within a prescribed space, nor finding delight in dancing and plaudits which have no sense in them. And after the observance of the Sabbath, let every friend of Christ keep the Lord's [Day, Dominicam] as a festival, the resurrection-day, the queen and chief of all the days.
there is historical evidence of some observance of the seventh-day Sabbath among the Waldenses. A report of an inquisition before whom were brought some Waldenses of Moravia in the middle of the fifteenth century declares that among the Waldenses "not a few indeed celebrate the Sabbath with the Jews."—Johann Joseph Ignaz von Dollinger, Beitrage zur Sektengeschichte des Mittelalters (Reports on the History of the Sects of the Middle Ages), Munich, 1890, 2d pt., p. 661. There can be no question that this source indicates the observance of the seventh-day Sabbath..
XXXIII. I Peter and Paul do make the following constitutions. Let the slaves work five days; but on the Sabbath day and the Lord's day let them have leisure to go to church for instruction in piety. We have said that the Sabbath is on account of the creation, and the Lord's day of the resurrection. Let slaves rest from their work all the great week, and that which follows it — for the one in memory of the passion, and the other of the resurrection; and there is need they should be instructed who it is that suffered and rose again, and who it is permitted Him to suffer, and raised Him again. Let them have rest from their work on the Ascension, because it was the conclusion of the dispensation by Christ. Let them rest at Pentecost, because of the coming of the Holy Spirit, which was given to those that believed in Christ. Let them rest on the festival of His birth, because on it the unexpected favour was granted to men, that Jesus Christ, the Logos of God, should be born of the Virgin Mary, for the salvation of the world. Let them rest on the festival of Epiphany, because on it a manifestation took place of the divinity of Christ, for the Father bore testimony to Him at the baptism; and the Paraclete, in the form of a dove, pointed out to the bystanders Him to whom testimony was borne. Let them rest on the days of the apostles: for they were appointed your teachers to bring you to Christ, and made you worthy of the Spirit. Let them rest on the day of the first martyr Stephen, and of the other holy martyrs who preferred Christ to their own life.
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