The Adversary, Heb: שָׂטָן, satan; Greek: Σατανᾶς, Satanas; is often associated with Beelzebub, meaning "Lord of the Flies", Lucifer, meaning "shining one", the King of Tyre, and Satanel, meaning "Adversary of God".
The original serpent, the first murderer, who rebelled against Jehovah in the Garden of Eden and possibly even seduced King David  to sin against Jehovah. (1 Chronicles Chapter 21) Since authority over the world was given to him, the adversary tempted Jesus to take the glory of all the kingdoms of the world. The adversary is also described in John's revelation as a great red dragon having seven heads.
 Then Jesus, full of holy spirit, turned away from the Jordan, and he was led about by the spirit in the wilderness+ 2 for 40 days, being tempted by the Devil. And he ate nothing in those days, so when they had ended, he felt hungry. 3 At this the Devil said to him: “If you are a son of God, tell this stone to become a loaf of bread.” 4 But Jesus answered him: “It is written, ‘Man must not live on bread alone.’”
 So he brought him up and showed him all the kingdoms of the inhabited earth in an instant of time. 6 Then the Devil said to him: “I will give you all this authority and their glory, because it has been handed over to me, and I give it to whomever I wish. 7 If you, therefore, do an act of worship before me, it will all be yours.” 8 In reply Jesus said to him: “It is written, ‘It is Jehovah your God you must worship, and it is to him alone you must render sacred service.’”
 He then led him into Jerusalem and stationed him on the battlement of the temple and said to him: “If you are a son of God, throw yourself down from here, 10 for it is written, ‘He will give his angels a command concerning you, to preserve you,’ 11 and, ‘They will carry you on their hands, so that you may not strike your foot against a stone.’” 12 In answer Jesus said to him: “It is said, ‘You must not put Jehovah your God to the test.’”
 So the Devil, having finished all the temptation, departed from him until another convenient time.
Ruler of the worldEdit
“Now there is a judging of this world; now the ruler of this world will be cast out.” - John 12:31
“I will not speak with you much more, for the ruler of the world is coming, and he has no hold on me.” - John 14:30
“...then concerning judgment, because the ruler of this world has been judged.” - John 16:11
‘And do not bring us into temptation, but deliver us from the wicked one.’ - Matthew 6:13
“Where anyone hears the word of the Kingdom but does not get the sense of it, the wicked one comes and snatches away what has been sown in his heart; this is the one sown alongside the road.” - Matthew 13:19
“I do not request that you take them out of the world, but that you watch over them because of the wicked one.” - John 17:15
“We know that we originate with God, but the whole world is lying in the power of the wicked one.” - 1 John 5:19