Mark 1:23-24

Just then there was a man in their synagogue with an unclean spirit; and he cried out saying, “What business do You have with us, Jesus of Nazareth? Have you come to destroy us? I know who You are- the Holy One of God!”

It is a blindness and rebellion not to believe that God exists and that Jesus is His son. The demons and unclean spirits knew Jesus as the Son of God. A man struggles because of a lack of knowledge, offense, or pride, which causes rebellion against God. God can still change man’s heart; we must keep praying for the lost.