Angel Of Light
Satan, as the Anti-Christ Spirit, has been masquerading as an Angel of Light, and he has been given power to deceive many even the "very elect" if it were possible in these last days.
"And no marvel; for even Satan fashioneth himself into an angel of light."(2 Corinthians 11:14)

"For there shall arise false Christs, and false prophets, and shall shew great signs and wonders; insomuch that, if it were possible, they shall deceive the very elect." (Matthew 24:24)
The word "light" in the above scripture is the Greek work "phos" meaning - to shine or to make manifest. From this root word also comes the word "photizo: as in 1 Corinthians 4:5 "to bring to light the hidden things of darkness, and make manifest"
1) to give light, to shine
2) to enlighten, light up, illumine
3) to bring to light, render evident
a) to cause something to exist and thus come to light and become clear to all
4) to enlighten, spiritually, imbue with saving knowledge
a) to instruct, to inform, teach
b) to give understanding to
With the above definition of Greek word for "light" we can understand that 2 Cor. 11:14 is saying that Satan comes as an angel of light, giving a false "understanding" of spiritual things.  

Paul had to deal with the false "angel of light" in his day, but said it would become much worse in the last days. Even as Jesus himself warned: "For there shall arise false Christs, and false prophets, and shall show great signs and wonders; so as to lead astray, if possible, even the elect."(Matthew 24:24)
"Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils;"(1 Timothy 4:1)

"This know also, that in the last days perilous times shall come." (2 Timothy 3:1)
We know that in these last days God will be shedding more light and revealing truth that had previously been hidden.  Many things have been "sealed" until the "time of the end".  God revealed mysteries to Paul that had been "kept secret" to all previous generations , he wrote:
"...the preaching of Jesus Christ, according to the revelation of the mystery, which was kept secret since the world began," (Romans 16:25)

" that by revelation was made known unto me the mystery, as I wrote before in few words, whereby, when ye read, ye can perceive my understanding in the mystery of Christ; which in other generations was not made known unto the sons of men, as it hath now been revealed unto his holy apostles and prophets in the Spirit;" (Ephesians 3:3-5)
Revelation means to bring to light that which was hidden, disclosure of truth, instruction concerning things before unknown.  Things that Daniel wrote about thousands of years ago have been sealed until our time. 
"But thou, O Daniel, shut up the words, and seal the book, even to the time of the end: many shall run to and fro, and knowledge shall be increased." (Daniel 12:4)
As Paul said in 2 Timothy 3:1, these are perilous days we are in. And as God is revealing truth to his body, Satan will try to deceive "even the elect" if he can with His own brand of the "truth". Satan has had 2000 years to perfect masquerading as this angel of light. There has been a great falling away from the truth of the Gospel of the Kingdom as it was first preached by Jesus and the apostles. God is now returning the truth of this Gospel to his people.  It is the power that can transform us into that a people He is looking for, it is a "church" without spot or wrinkle.

It will not be easy to deceive those who seek Christ for truth; Satan will have to cloak the deception in the midst of much truth, becoming a master of deception as the "angle of light".  I believe He will use the scriptures as His biggest tool to try to deceive the elect, he knows them well and knows how to twist them.  He will put scriptures together and make it seem logical and right, but will be doctrines of devils.  Those who are not willing to lay down ALL other props for guidance, rather than trusting in Christ to being led by His Spirit and have not received a love of the truth no matter what it might cost them, will be deceived in one fashion or another.
"Beware lest any man spoil you through philosophy and vain deceit, after the tradition of men, after the rudiments of the world, and not after Christ." (Colossians 2:8)
The word for today is BEWARE. Beware of the traditions and "religions" of men. Beware of the "rudiments" of the world.  A definition of "rudiments" is:  a statement of fundamental facts or principles.  It is human reasonings rather that being led by Christ.  If we hold to any of these things, our traditional way of doing things, with even our own understanding of scripture if it is contrary to the leading of the Holy Spirit, it will become an "idol of our heart" and will leave us open to deception.  There is no other sure foundation than Christ and being led by His Spirit.  If we look to anything else besides Him, it will become a stumbling block for us and we will not see the truth and will be deceived.  God will give us over to believe this counterfeit "angel of light" and will believe the lie unto our own destruction.
(Ezekiel 14:4) "Therefore speak unto them, and say unto them, Thus saith the Lord Jehovah: Every man of the house of Israel that taketh his idols into his heart, and putteth the stumblingblock of his iniquity before his face, and cometh to the prophet; I Jehovah will answer him therein according to the multitude of his idols;"
In these last days there will be wonderful revelations from the Lord returning us to true holiness, and pure word from Him.  We must judge all things through Christ and He will be faithful to lead us to the "Life" that manifests His nature...the "church" without spot or wrinkle.
"But he that is spiritual judgeth all things, yet he himself is judged of no man. For who hath known the mind of the Lord, that he may instruct him? But we have the mind of Christ." - (1 Corinthians 2:15-16)