There are many, many definitions for ‘Pagan’ religion. There are also many varieties of pagan religions. A pagan religion is blamed for the destruction of Sodom and Gomorrah, but it was more than just their religion. Their behavior and practices were also a part of the reason why the cities of Sodom and Gomorrah were destroyed.

This scripture explains part of the reason for the destruction. The destruction of Sodom and Gomorrah became an example in the Bible of how God judges sin. “Now this was the sin of your sister Sodom: she and her daughters were arrogant, overfed and unconcerned; they did not help the poor and needy. They were haughty and did detestable things before Me. Therefore I did away with them as you have seen” (Ezekiel 16:49-50).

Further explanation shows that God tried to save the cities – In Genesis 18, God told Abraham that he planned to destroy the city of Sodom because of its gross immorality. Abraham pleads with God not to destroy Sodom, and God agrees that he would not destroy the city if there were 50 righteous people in it, then 45, then 30, then 20, or even 10 righteous people. Documentation goes on to show that no righteous people could be found.
Classical Jewish texts do not indicate that God destroyed Sodom and Gomorrah because the inhabitants were homosexual. Rather, because the inhabitants were generally depraved and uncompromisingly greedy. Rabbinic writings affirm that the primary crimes of the Sodomites were terrible and repeated economic crimes, both against each other and outsiders. Another rabbinic tradition is that these two wealthy cities treated visitors in a sadistic fashion. One example is the story of the “bed” that guests to Sodom were forced to sleep in: if they were too short they were stretched to fit it, and if they were too tall, they were cut up. The Talmud also recounts the incident of a young girl (some sources say it was a daughter of Lot) who gave some bread to a poor man who had entered the city. When the townspeople discovered her act of kindness, they smeared her body with honey and hung her from the city wall until she was stung to death by bees.
These examples show that their religious beliefs were not the real issue. It was the horrendous behavior and their lack of repentence for the things they did.