Complex sentence: Baal Peor was a Canaanite form of the Baals, god of fertility and virility, being his cult especially characterised by sexual indulgence and licentiousness.
Split into simpler sentences: Baal Peor was a form of the Canaanite god, Baal, representing the principles of fertility and virility. The cult devoted to him was characterised by sexual indulgence and licentiousness.