Sunday, with the exception of a single extreme group of Ebionites mentioned by Eusebius of Caesarea; and that there is no evidence that Sunday was observed as substitute Sabbath worship in the early centuries. Some Protestant scholars have argued that Christian Sunday worship traces back even further, to the resurrection appearances of Jesus recorded in the Gospel narratives where Jesus would appear to his disciples on the first day of the week. Seventh-day Adventist scholar Samuele Bacchiocchi has argued that Sunday worship unconnected to the Sabbath was introduced in Rome in the 3rd century, and was later enforced throughout the Christian church as a substitution for Sabbath worship. Edict of Constantine On 3 March 321, Constantine I decreed that Sunday (dies Solis) will be observed as the Roman day of rest [CJ3.12.2]: In this, Constantine's decree gave civil sanction to the common practice of the Christian Church and was designed to promote Christianity throughout his empire. Middle Ages Augustine of Hippo followed the early patristic writers in spiritualizing the meaning of the Sabbath commandment, referring it to eschatological rest rather than observance of a literal day. However, the practice of Sunday rest increased in prominence throughout the early Middle Ages. Thomas Aquinas taught that the decalogue is an expression of natural law which binds all men, and therefore the Sabbath commandment is a moral requirement along with the other nine. Thus Sunday rest and Sabbath became increasingly associated. Following Aquinas' decree, Christian Europeans could now spend less time denouncing the Judaistic method of observing the Sabbath, instead establishing rules for what one "should" and "should not" do on the Sabbath. For example, while the Medieval Church forbade most forms of work on the Sabbath, it allowed "necessary works", and priests would allow their peasants to perform the needed agricultural work in the field. Modern church Reformed The Heidelberg Catechism of the Reformed Churches founded by John Calvin, teaches that the moral law as contained in the Ten Commandments is binding for Christians and that it instructs Christians how to live in service to God in gratitude for His grace shown in redeeming mankind. The doctrine of the Christian Reformed Church in North America thus stipulates "that Sunday must be so consecrated to worship that on that day we rest from all work except that which charity and necessity require and that we refrain from recreation that interferes with worship." Sunday