Longer Catechism (Orthodox) 3.108

Chapter 3 — Part I — Article I (Of God the Father)

Section 108. Q. How came they to be evil? A. They were created good, but they swerved from their duty of perfect obedience to God, and so fell away from him into self-will, pride, and malice. According to the words of the Apostle Jude, they are the angels which kept not their first estate, but left their own habitation. Jude 6.