The holiness of the Catholic Church is no argument. Satan pretends to be an Angel of Light.

The Catholic Answers

Satan is said to be an angel of light in so far as he makes evil appear to be good, not that he ever inspires real good. He never inspires people to hate sin and to love God as does the Catholic Church.

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty