A study of ancient history reveals that the cross was used as a religious symbol long before the first century A.D.—when Jesus Christ walked the earth, was crucified and resurrected. The Bible does not record the use of the cross as a physical religious symbol in either the Old or New Testaments. But historical records of other civilizations do make record of the cross as a symbol.

It is a historical fact that the cross has been used as a symbol of pagan religions going back to antiquity. Further study reveals that the cross can be found in the ancient religions of Babylon, India, Syria, Egypt, Rome and other ancient pagan cultures.

It is very clear, based on history, that the cross was used to represent and worship the false gods of many cultures and religions.

https://lifehopeandtruth.com/bible/10-commandments/idolatry-second-commandment/is-it-okay-to-wear-a-cross/