Many try to dismiss the fact that the Bible declares that there is a very real spiritual being called Satan. Various names are given to Satan, including: the devil (Greek diabolos), serpent/snake, “Abaddon,” “Beelzebub” and “Belial.” His name means adversary and deceiver. He is also described as “a liar and the father of lies,” “a murderer from the beginning,” and that “there is no truth in him” (John 8:44). He is your “accuser” before God (Revelation 12:1, Job 1) and “the prince of the power of the air [this fallen world]” (Ephesians 2:1-2). Note however, that he is not called “Lucifer” (see the Lucifer as the Devil false teaching).
The Bible doesn’t tell us exactly when Satan was created, but it does say that he is a very real created spiritual being, an angel. As a created being, he is therefore not omniscient (all knowing), omnipresent (able to be everywhere at once) or impotent (all powerful). And it tells us that he “prowls around like a roaring lion, seeking someone to devour” (1 Peter 5:8). So yes, Satan exists, and he means to destroy you – to kill you eternally. He tries to do this by obfuscating the truth of Scripture, by telling lies, half-truths, and distorting (mis-quoting) Scripture. He is the father of lies. Below is an excerpt from Beyond the Tomb: 
Satan opposes everything good and of God. His main weapon today is deception. The false teachings in this section of the book are of his doing, as he attempts to deceive people out of believing in God, in the Bible, in Christ, and then even after they are born again, to try to cause them to stumble and fall away from the faith, backslide, go apostate or be lured out of the straight and narrow path to eternal life and back into bondage under sin to eternal death.
The popular rendition of him as a fanciful cartoon character with horns in red tights and a pitch fork is woefully off the mark and designed again to deceive you into dismissing and underestimating the fact that he is a very real being, and that he means your eternal death. The forces of evil are in a battle with the forces of God and good, and this world is the battleground. We as Christians are on the front line in a spiritual war, with Satan and the angels who sinned on one side, and God and His holy angels and saints on the other side. Do not make the mistake of underestimating Satan, nor make the mistake of pretending he doesn’t exist. Both mistakes can lead you to eternal death.