The answer from God’s word:
“Because of God’s incarnation, Satan makes every attempt to accuse and wants to attack God by doing so. However, God does not retreat on that account, and He just speaks among men and works among men, letting men know Him through the incarnate flesh. But Satan’s eyes turn red with anxiety, and it also puts in a lot of efforts on the people, trying to make them become passive, draw back, and even get lost.”
from “The Interpretation of the Thirteenth Utterance”
“What God wants to do on men is exactly what Satan wants to destroy. What Satan wants to destroy is ‘expressed’ through men, without any concealment. For what God does on men, there is an obvious demonstration, which is that men’s condition is better and better; for what Satan destroys on men, there is also an obvious representation, which is that men become more and more fallen and their condition becomes more and more lowered, and the serious ones will be taken captive by Satan.”
from “The Interpretation of the Fifteenth Utterance”
“Satan comes into the flesh of man to stir up disturbance, and uses the flesh of man to disturb the work of God, and impair the plan of God, and thus man has become Satan, and the enemy of God.”
from “Corrupt Mankind Is More in Need of the Salvation of God Become Flesh”
“1 God works to make man understand more truths and know more about God’s disposition. In the end, man gains knowledge of God and is willing to die for God and live for God. But those weaknesses in man are still in the control and grasp of Satan, which can still make man suffer. Evil spirits can still work on man to disturb him, causing him to be out of his senses, disordered in his mind, upset in his heart, or disturbed in every respect. There are still things of mind and soul within man that can be controlled and manipulated by Satan.
2 So, you may have sicknesses and worries and may possibly seek death or hang yourself. And you may also feel the world is desolate, and feel it is meaningless to live. That is to say, these sufferings of man are still in Satan’s grasp. This is man’s fatal spot. This is man’s fatal spot.”
from “351 The Significance of God’s Undergoing Sufferings in Man’s Stead”
“In every step of work that God does within people, externally it appears to be interactions between people, as if born of human arrangements, or from human interference. But behind the scenes, every step of work, and everything that happens, is a wager made by Satan before God, and requires people to stand firm in their testimony to God. Take when Job was tried, for example: Behind the scenes, Satan was making a bet with God, and what happened to Job was the deeds of men, and the interference of men. Behind every step that God does in you is Satan’s wager with God—behind it all is a battle. … When God and Satan do battle in the spiritual realm, how should you satisfy God, and how should you stand firm in your testimony to Him?”
from “Only Loving God Is Truly Believing in God”
