Paul wrote to Timothy and told him that in the last days before the Rapture or the Catching away of the Church that there would be some that would depart from the faith giving heed to suducing spirits and doctrines of devils (1 Tim. 4:1).
This was known to Paul as he was very much acquainted with the lies and deception of the Devil who was a powerful source against the Believers and Unbelievers as well.
As Believers we need to be on our guard against the deceptive powers of the enemy of our soul who is out to kill us spiritually.
If we allow even a small crack in our Armor it will allow the enemy to get in and begin to deceive us an turn us away from our fellowship with the Savior.
Beware, for we are living in those last days that Paul and John wrote about in the Book of Revelation, that we do not follow the lies and doctrines of the suducing spirits and devils.