That's a very good observation Brett. They definitely pre-date Constantine but as I survey the Fathers I'm still seeing a reaction against Judaism (some pretty intense) instead of any reference to a specific proclamation of the apostles. The writings of the Fathers are not really doctrinal training but rather a record of how early Christians worshipped. It's assumed that there must have been a precedent set by the apostles, but wouldn't an overturning of a creation ordinance call for a specific teaching from scripture? Would the Holy Spirit leave us to base our observation of Sunday as the sabbath to an assumption. Furthermore, would an apostle have the authority to change a creation ordinance in the first place? God declared it holy, Peter might have said that it isn't anymore. That's shakey ground. I could accept the change if it had been recorded in Holy writ by an inspired writer with close apostolic connection. When we protested against the mother church we took a good hard look at our traditions and measured them against scripture. I appreciate that the Seventh Day Baptists and others kept looking and dared to go against the economy and tradition to recognize that the sabbath had been changed without the authority to do so. Unfortunately, seventh day sabbath keepers share their convictions with many who could be described as cults. That casts our argument into suspicion from the start. I'm not trying to convert anyone, I'm just trying to share the wonderful gift of the sabbath.