Constantine the Great who was emperor of Rome joined the church and became a bishop. He enacted a law that first enjoined Sunday keeping in 321 AD.
Note: The earliest recognition of the observance of Sunday as a legal duty is a constitution of Constantine in 321 AD, enacting that all courts of justice, inhabitants of towns, and workshops were to be at rest on Sunday, with the exception in favor of those engaged in agricultural labor.
Encyclopedia Britannica 11th edition, “Sunday”
After this, other ordinances came in through human instrumentality. Most people today do not even realize that they are following a man made law first enacted in the fourth century. Is it any wonder that God said “Remember the Sabbath?”