Question 11
How did Sunday observance originate among Christians?
Bible
Daniel 7:25
Answer
Daniel foretold in prophecy that the antichrist (who is the same entity as the Beast in Revelation 13 and the Little Horn power in Daniel 7) would think to change God’s law about time.
The very 1st Sunday law on record came from Roman Emperor Constantine March 7, 321 AD after he made a supposed conversion to Christianity. Here is what he wrote: “Let all the judges and town people and the occupation of all trades rest on the venerable day of the sun (Dies Solis)". The next Sunday law came from the Council of Laodicea in 364 AD which stated that, "Christians must not Judaize by resting on Saturday.” Bishop Eusebius added, “All things whatsoever that it was duty to do on the Sabbath, these we have transferred to the Lord’s day.” (for references, just search any Encyclopedia for Constantine and Council of Laodicea)
“The Catholic Church designated Sunday as the day for corporate worship and gets full credit — or blame — for the change." This Rock, p. 8 June 1997, The Magazine of Catholic Apologetics and Evangelization