What causes Evil Spirits

Mark 1
21. Then they went into Capernaum, and immediately on the Sabbath He entered the synagogue and taught.
22. And they were astonished at His teaching, for He taught them as one having authority, and not as the scribes.
23. Now there was a man in their synagogue with an unclean spirit. And he cried out,
24. saying, "Let us alone! What have we to do with You, Jesus of Nazareth?
Did You come to destroy us? I know who You are the Holy One of God!"
NKJV

Exodus 20:
3 "You must not have any other god but me.
4 "You must not make for yourself an idol of any kind or an image of anything in the heavens or on the earth or in the sea.
5 You must not bow down to them or worship them, for I, the Lord your God, am a jealous God who will not tolerate your affection for any other gods. I lay the sins of the parents upon their children; the entire family is affected-even children in the third and fourth generations of those who reject me.
NLT

When the people of Israel had cried out to God to take them out of terrible bondage in Egypt, God had done so, and they had come into a relationship with Him where, if they obeyed His commandments, they would be protected from evil.

One of the commandments God gave them in Exodus is stated for us above: they were to worship only Almighty God and no other. The reason for this is that whoever is worshipped is given power over the worshipper and his descendents for the next 4 generations.

If you worship the God of the Bible, then you come under His blessings and these blessings flow down 4 generations. But if you worship another god, curses follow you and the next 4 generations of your family, and through these curses evil spirits gain access to your family line.

There are all kinds of evil spirits. The particular kind of evil spirit bothering the man in the synagogue that day, was an unclean spirit. This kind of evil spirit opens the life to practices and attitudes that pollute the life in spirit, soul and body. It makes a person unable to be completely holy and blameless in God's presence.

That is why the unclean spirit could not keep quiet in the presence of the Lord Jesus. Jesus, being the God-man, was sinlessly holy, and the unclean spirit was so uncomfortable in His presence that it was forced to identify itself in public, where before it had been able to hide and destroy the man's life undetected by the religious leaders of the synagogue.

Prayer:
Father, today I ask that through the blood of Jesus, You cleanse me from all ancestral uncleanness that I have inherited, and also from any uncleanness that I have invited into my life. My desire is to come into Your presence free and unhindered,
in the name of Jesus
Amen.