Question:
Can angels sin?

Answer:
Yes, when Satan, the devil, was created he was the highest of the angels, but he sinned: “The devil sinneth from the beginning” (1 John 3:8). Satan was “The anointed cherub that covereth” and “wast perfect in his ways from the day that he wast created, till iniquity was found in him …. his heart was lifted up because of his beauty” (Ezekiel 28:14, 15, 17). And he said: “I will ascend above the heights of the clouds; I will be like the most High” (Isaiah 14:14).

See also Revelation 12:10 and 2 Corinthians 11:14. In Genesis 3 Satan tempted Eve the same way that he fell by telling her: “You shall be as gods” (Genesis 3:5). 2 Peter 2:4 says, “God spared not the angels that sinned, but cast them down to hell [Gr: Tartarus—deepest pit of gloom], and delivered them into chains of darkness, to be reserved unto judgment.”