According to the Bible, there is a very simple answer. Posing as “an angel of light,” Satan the Devil has misled millions into following his teachings rather than God’s. (2 Corinthians 11:14) The apostle John showed that Satan’s influence is so extensive that “the whole world is lying in the power of the wicked one.” (1 John 5:19) John knew that Satan was “misleading the entire inhabited earth.”—Revelation 12:9.
What have been the consequences of this? Satan has promoted religious systems that on the surface appear to be holy. They have “a façade of ‘religion,’” but their true condition is exposed by the evil fruitage they produce. (2 Timothy 3:5, J. B. Phillips; Matthew 7:15-20) Instead of helping to solve mankind’s problems, religion actually becomes part of the problem.
Do not quickly dismiss that idea as being farfetched or unreasonable. Remember, the very nature of deception is that the one being deceived is unaware of it. The apostle Paul gave an example of this when he wrote: “The things which the nations sacrifice they sacrifice to demons, and not to God.” (1 Corinthians 10:20) Those people would likely have been shocked to think that they were worshiping demons. They thought that they were worshiping a good god, or gods, of some kind. Yet, in reality they had been deceived by “wicked spirit forces in the heavenly places,” who support Satan in his efforts to mislead mankind.—Ephesians 6:12.
Let us consider, for example, how Satan managed to deceive and mislead many professed Christians who chose to ignore the apostle John’s warning about that evil influence.—1 Corinthians 10:12.