The vital importance of knowing and being obedient to God's word cannot be overstressed as it guarantees protection from the greatest deception planet Earth is facing and will continue to face for some time.
What is this deception? Jesus repeatedly and forcefully warned his disciples that, "...there shall arise false Christs, and false prophets, and shall show great signs and wonders; insomuch that, if it were possible, they shall deceive the very elect. Behold, I have told you before. Wherefore, if they shall say unto you, Behold he is in the desert; go not forth, behold, he is in the secret chambers; believe it not. For as the lightning cometh out of the east, and shineth even unto the west; so shall also the coming of the Son of man be" (KJV, Matthew 24:-27).
The great and terrible deception is the following of a false Christ who possesses great supernatural power to perform signs and wonders to convince people to believe he is God. The scripture above reveals much valuable information about the great lie that so many will believe. First, it should be observed that the manifestation of diabolical power that the false Christ will display will not be distinguishable by the natural eye or reasoning. This is why he would be able to deceive the very elect of God if they made the decision to follow him based purely on what their eyes witness.
The reasons why so many will be deceived into following such false Christs and prophets vary. However, many of these people have willfully rejected the true Christ, closing their eyes to his word and covering their ears to not hear his voice. They invited the hardening of their hearts just as the Egyptian pharaoh did when he refused to let the children of Israel go. This is why the Bible warns the reader to respond to God's conviction while his conscious is still intact (Exodus 7:3, Hebrews 3:8).
Far too many people do not realize that there is a point of no return regarding salvation. Scripture gives a frightful warning to such individuals. 2 Thessalonians 2:9-12 says, "even him, whose coming is after the working of Satan with all power and signs and lying wonders. And with all deceivableness of unrighteousness in them that perish, because they received not the love of the truth, that they might be saved. And for this cause God shall send them strong delusion (deception), that they should believe a lie, that they all might be damned who believed not the truth, but had pleasure in unrighteousness.
Recommended reading: Jesus Or His Impostor?