5 Bible Verses about Fallen Angels

O how you have fallen from heaven, you morning star (shining one), and son of the dawn! How you have been cut down to the ground, you who conquered nations! You thought: 'I will go up to heaven (Mount Zion) and set up my throne above God's stars (messengers). I will sit on the mountain of meeting far away in the north where the gods assemble. I will go above the top of the clouds. I will be like the Most High.'read more.
But you have been brought down to the grave, to the deepest part of the pit.

He said to them: I saw Satan falling like lightning from heaven.

War broke out in heaven. Michael and his angels fought against the dragon and his angels. The dragon lost and no place in heaven was found for him any longer. The great dragon was thrown down, that old serpent, called the Devil, and Satan, who deceives the whole world. He was hurled down to the earth, and his angels with him.read more.
I heard a loud voice saying in heaven, Now has come the salvation, and strength, and the kingdom of our God, and the power (authority) of his Christ: for the accuser of our brothers has been thrown down, who accused them before our God day and night. They conquered (overcame) him by the blood of the Lamb, and by the word of their testimony; and they did not love their lives when faced with death. Therefore rejoice (be glad), you heavens, and you that dwell in them. But woe to the earth and the sea! For the devil has come down to you, having fierce anger, because he knows that he has only a short time. When the dragon saw that he was thrown to the earth, he persecuted the woman who gave birth to the male-child. Two wings of a great eagle were given to the woman, that she might fly into the wilderness, into her place, where she is nourished for a time, and times, and half a time (one thousand two hundred and sixty days), out of the serpent's reach. The serpent spewed water out of his mouth like a flood after the woman, that he might cause her to be carried away by the flood. But the earth rescued the woman, and the earth opened its mouth, and swallowed up the flood that the dragon spewed out of his mouth. The dragon was furious with the woman and waged war with the remnant of her seed. These are the ones who obey the commandments of God and have the testimony of Jesus Christ.

God did not spare angels when they sinned, but cast them down to captivity in pits of darkness reserved for judgment!