Answer
Satan is God’s great enemy, and therefore the enemy of Christians as well. Among several other names, Satan is known as the accuser.
Satan was formerly a beautiful and powerful cherub, likely the highest of all angels. But iniquity was found in him (Ezekiel 28:15), and he was lifted up in pride, desiring to be greater than the Lord God (Isaiah 14:12–15). He led an army of angels into rebellion, which resulted in his ejection from heaven—along with every angel who had followed him (Ezekiel 28:17–18). Now Satan prowls the earth, seeking to hinder all he can from choosing salvation and living a life of obedience (1 Peter 5:8). In addition, Satan acts as the accuser of believers in an attempt to discredit them before God.
For the time being, God has allowed Satan the accuser limited access to heaven. In the book of Job, we see Satan stand before God and accuse a righteous man named Job, claiming that Job is only faithful because God had blessed him abundantly (Job 1:9–10). Satan posits that, if Job is put to the test, he would eventually turn from God and forsake his righteous life (verse 11; 2:4–5). In His omniscience, God knows that Job will remain steadfast, and He gives Satan the accuser permission to test Job.
The book of Revelation tells us a bit more about Satan’s role as accuser: “Then I heard a loud voice in heaven say: ‘Now have come the salvation and the power and the kingdom of our God, and the authority of his Messiah. For the accuser of our brothers and sisters, who accuses them before our God day and night, has been hurled down’” (Revelation 12:10). Satan is relentless in his accusations—he accuses God’s children continually. He hates God and all that God is, which means he also hates God’s mercy and forgiveness extended to sinful humanity. Satan the accuser stands before God in an attempt to somehow lessen God’s love or diminish God’s mercy. Fortunately, his accusations against us fall on deaf ears: “Who will bring any charge against those whom God has chosen? It is God who justifies” (Romans 8:33). Salvation belongs to the Lord, and His justification cannot be reversed. God is greater than our accuser.
Satan the accuser desires to remind believers of their sin and their unworthiness of a place in God’s family and in this way sow doubt into their hearts and minds. Satan wants to make Christians fear for their salvation and forget God’s love and faithfulness. Satan says, “Look at your sinfulness”; God says, “Look to Jesus, the author and finisher of your faith” (see Hebrews 12:2).
In spite of Satan’s accusations and deceptions, God will not change His mind about those He has called to salvation (Romans 8:38–39). He has set the accuser’s ultimate fate: “And the devil, who deceived them, was thrown into the lake of burning sulfur, where the beast and the false prophet had been thrown. They will be tormented day and night for ever and ever” (Revelation 20:10). After God creates the new heaven and new earth, Satan will be absent for eternity (Revelation 21:1–4, 27). Believers can rest in the knowledge that our salvation is sure (Romans 11:29; Ephesians 1:13–14) and take comfort in the promise that God will complete the good work He began in us (Philippians 1:6).
In his book The Pilgrim’s Progress, John Bunyan describes a battle between the accuser, Apollyon, and Christian in the Valley of Humiliation. One of Apollyon’s ploys is to recite a laundry list of Christian’s sins: “Thou didst faint at first setting out, when thou wast almost choked in the Gulf of Despond; thou didst attempt wrong ways to be rid of thy burden, whereas thou shouldst have stayed till thy Prince had taken it off; thou didst sinfully sleep and lose thy choice thing; thou wast also almost persuaded to go back at the sight of the lions; and when thou talkest of thy journey, and of what thou hast heard and seen, thou art inwardly desirous of vain-glory in all that thou sayest or doest.”
Christian’s response to the accuser is full of humility and faith: “All this is true; and much more which thou hast left out: but the Prince whom I serve and honour is merciful and ready to forgive. But besides, these infirmities possessed me in thy country; for there I sucked them in, and I have groaned under them, been sorry for them, and have obtained pardon of my Prince.” At the mention of Christ’s forgiveness, Apollyon flies into a rage; Satan the accuser cannot abide the fact that his accusations are overcome by the grace of God in Christ.