The Scriptures reveal that, as "the god of this age"(2 Corinthians 4:4 2 Corinthians 4:4In whom the god of this world has blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine to them.
American King James Version×), the devil has assembled a vast multitude of human assistants. Most of these are mere followers. But far too many of his followers are also deceived religious teachers.
Paul explains the connection between them and the devil: "For such are false apostles, deceitful workers, transforming themselves into apostles of Christ. And no wonder! For Satan himself transforms himself into an angel of light. Therefore it is no great thing if his ministers also transform themselves into ministers of righteousness, whose end will be according to their works" (2 Corinthians 11:13-14 2 Corinthians 11:13-14  For such are false apostles, deceitful workers, transforming themselves into the apostles of Christ.
 And no marvel; for Satan himself is transformed into an angel of light.
American King James Version×).
Blinded by false but popular doctrines and traditions that have passed from one generation to another, these deceived teachers are among Satan's most influential tools of deception. He uses them to cleverly disguise his ways as God's ways and lead people astray.
Some of these leaders, and the institutions they serve, are obviously based on nonbiblical concepts. In other words, their beliefs are secular or pagan in origin. They make no pretense of following the Holy Scriptures.
But many others are counterfeits of the Church Jesus established. Jesus Himself predicted that false teachers would rise up who would "deceive many" (Matthew 24:5-24 Matthew 24:5-24  For many shall come in my name, saying, I am Christ; and shall deceive many.
 And you shall hear of wars and rumors of wars: see that you be not troubled: for all these things must come to pass, but the end is not yet.
 For nation shall rise against nation, and kingdom against kingdom: and there shall be famines, and pestilences, and earthquakes, in divers places.
 All these are the beginning of sorrows.
 Then shall they deliver you up to be afflicted, and shall kill you: and you shall be hated of all nations for my name's sake.
 And then shall many be offended, and shall betray one another, and shall hate one another.
 And many false prophets shall rise, and shall deceive many.
 And because iniquity shall abound, the love of many shall wax cold.
 But he that shall endure to the end, the same shall be saved.
 And this gospel of the kingdom shall be preached in all the world for a witness to all nations; and then shall the end come.
 When you therefore shall see the abomination of desolation, spoken of by Daniel the prophet, stand in the holy place, (whoever reads, let him understand:)
 Then let them which be in Judaea flee into the mountains:
 Let him which is on the housetop not come down to take any thing out of his house:
 Neither let him which is in the field return back to take his clothes.
 And woe to them that are with child, and to them that give suck in those days!
 But pray you that your flight be not in the winter, neither on the sabbath day:
 For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be.
 And except those days should be shortened, there should no flesh be saved: but for the elect's sake those days shall be shortened.
 Then if any man shall say to you, See, here is Christ, or there; believe it not.
 For there shall arise false Christs, and false prophets, and shall show great signs and wonders; so that, if it were possible, they shall deceive the very elect.
American King James Version×). This counterfeit Christianity began during the lifetime of Christ's apostles (Galatians 1:6-7 Galatians 1:6-7  I marvel that you are so soon removed from him that called you into the grace of Christ to another gospel:  Which is not another; but there be some that trouble you, and would pervert the gospel of Christ.
American King James Version×). Peter warned faithful Christians: "But there were also false prophets among the people, even as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Lord who bought them, and bring on themselves swift destruction. And many will follow their destructive ways, because of whom the way of truth will be blasphemed" (2 Peter 2:1-2 2 Peter 2:1-2  But there were false prophets also among the people, even as there shall be false teachers among you, who privately shall bring in damnable heresies, even denying the Lord that bought them, and bring on themselves swift destruction.  And many shall follow their pernicious ways; by reason of whom the way of truth shall be evil spoken of.
American King James Version×).
The devil plays an immense role in the religions of mankind. Only those who ask for God's help, as they diligently study the Bible and compare their beliefs to what it teaches, can hope to overcome the deceptions that are so prevalent in today's religious organizations and fellowships.