Please note: I am bringing to your attention the position of our Holy Orthodox Christian Church on the existence of Satan, demons and the spiritual warfare that is taking place in our lives and our world. The greatest of all satanic deception is that he does not exist and therefore there is no evil or hell or sin or spiritual death.
When our Savior Jesus Christ taught us how to pray, He did not say to ask for deliverance from evil, but specifically, “deliver us from the evil one (Πειρασμόν). For, in this life we are often subjected to evil, and those who actually struggle to follow Christ and His Holy Orthodox Christian Faith must often endure it. Indeed, in the Beatitudes, we are even assured that we must endure evil. Moreover, in this world, evil often seems to triumph over good. Christ came to redeem us from our bondage to the prince of this world, to deliver us from bondage to his world of the materialism and sensuality. Our Savior has given us His Holy Orthodox Church as the vessel of our deliverance, and this freedom awaits those who will accept it and struggle for it according to the way God has provided for us.
In addition to the created spiritual powers who the will of God, the Angels, there are, according to the Orthodox Christian faith, those who rebel against Him and do evil. These are the demons or devils (which means literally those who “tear apart” and destroy) who are also known both in the Old and New Testaments as well as in the lives of the saints of the Church.
Satan (which means literally the enemy or the Adversary) is one proper name for the devil, the leader of the evil spirits. He is identified as the serpent symbol of Genesis 3 and as the tempter of both Job and Jesus (Job 1:6; St. Mark 1:33). He is labeled by Jesus Christ as a deceiver and liar, the “father of lies” (St. John 8:44) and the “prince of this world” (St. John 12:31; 14:30; 16:11). He has “fallen from heaven” together with his evil angels to do battle with God and His servants (St. Luke 10:18; Isaiah 14:12). It is this same Satan who “entered Judas” to effect the betrayal and destruction of Christ (St. Luke 22:3).
The Holy Apostles of Christ and the Saints of the Church knew from direct experience Satan’s powers against man for Man’s own destruction. They knew as well Satan’s lack of power and his own ultimate destruction when man is with God, filled with the Holy Spirit of Christ. According to Orthodox theology and doctrine there is no middle road between God and Satan. Ultimately, and at any given moment, man is either with God or the devil, serving one or the other. The ultimate victory belongs to God and to those with Him. Satan and his hosts are finally destroyed.
It is imperative to understand that without this recognition–and still more-the experience of this reality of the cosmic spiritual struggle (God and Satan, the good Angels and the evil angels), one cannot truly be called an Orthodox Christian who sees and lives according to the deepest realities of life. Once again, however, it must be clearly noted that the devil is not a “red-suited being” nor any other type of grossly-physical tempter. He is a subtle, intelligent spirit who acts mostly by deceit and hidden actions, having as his greatest victory man’s disbelief (atheism, skepticism, denial, rationalism etc.) in his existence and power. Thus, the devil attacks “head-on” only those whom he can deceive in no other way: Jesus and the greatest of the Saints. For the greatest part of his warfare he is only too satisfied to remain concealed and to act by indirect methods and means.
“Be sober, be watchful. Your adversary, the devil, prowls around like a roaring lion seeking someone to devour” (1 Peter 5:8).
“Put on the whole armor of God, that you may be able to stand against the wiles of the devil. For we are not contending against flesh and blood, but against the principalities, against the powers, against the world rulers of this present darkness, against the spiritual hosts of wickedness in the heavenly places” (Ephesians 6:11-12). (Source: Orthodox Church in America)