In most of the catholic cathedrals, the pictures of Jesus and Mary are also depicted with a round sun disc around their heads, symbolizing the supreme sun god
The Julian calendar in the year 46 BC (before Christ), which had the worship of the Egyptian sun god on a Sunday,
and in the year 325 AD the Roman empire made a law that commanded and forced the Christian movement to change their day of worship from the 7th day
(which falls on a Saturday on the Gregorian calendar) and move it to a Sunday (the day dedicated to the sun god).
In the year of 1582, Pope Gregory XIII of Rome, did some slight changes on this calendar, and he renamed it, and changed its name to the Gregorian calendar.
Today most of the biggest part of the world (Europe, Africa, America etc), uses the Gregorian Roman calendar as the astrological system which predicts their time and seasons.
Daniel 7:25 says: He shall speak pompous words against the Most High, Shall persecute the saints of the Most High,