Complex sentence: In old Jewish lore pagan gods of neighbouring cultures were classed as the worst of spirits in order to protect Jews from worshiping them-so Baal and Astarte were among the worst enemies of God.
Split into simpler sentences: In old Jewish lore, pagan gods of neighbouring cultures were classed as the worst of spirits in order to protect Jews from worshiping them. So, Baal and Astarte were among the worst enemies of God.