And how much Islamic religious knowledge would the average peasant or urban-dweller have possessed before the modern-era? Would a peasant or artisan in something like 12th century Damascus even have thought of prostitution or homosexuality as being sinful? Or would knowledge of what constitutes sin been restricted only to the religious class?
Hello,
The concept of taverns and brothels in the wider Islamic world has a different context than what you would find in Europe. There were certainly meeting places and later on, coffee shops, but brothels were never quite that open.
Homosexual relationships were not tolerated although they are written about in poetry. Remember, being Gay/Lesbian in a completely religious sense, is not wrong. Acting on those feelings and acts which define homosexuality is, in a religious sense, wrong and hence why people were punished.
I would not say that the Ulema was weaker. The Ulema were considered a strong foundation for the state and their support of the state was one of the pillars that the state could be legitimised from. Certainly stronger Khans, Khagans, Sultans, Emirs, and such could potentially execute certain individuals from the Ulema class or removed from their position but their reliance on the Ulema continually existed. See the Ottoman empire and how the Ulema was important to the state or even in Moghulistan during the Late Chagataiyid Khanate where a Khan kept killing members of the Ulema until he could find one that would allow him to marry his stepmother. This incident is found in the Tarikh-i-Rashidi translated by N. Elias and D. Ross:
Not long after this, the Khan fell in love with one of his father's wives and in consequence tried to obtain permission from the Ulama for an alliance with her. He put to death seven of the Ulama in succession, who decided against the union. At length the Khan came to Maulana Muhammad Attar, reeling with drunkenness and with a sword in his hand, and said to him "I want to marry my own mother; is it lawful or not?" The Maulana, who was one of the most learned of the darvishes and a most pious man, said to the Khan: "For such a one as you it is lawful."
The strength of the Ulema was also vital for 12th-16th century Delhi Sultanate where the religious class was vital to provide the Mamluks and later Sultans legitimacy and they were often given leeway to enact rules. So I would not define it as historically weaker, but rather it is historically weak in the contemporary world than previously.
Regarding knowledge, the school curriculum was composed of Religious teachings and thus those who could afford it were taught religious texts as well as non-religious texts. Hence the Urban dweller would have some knowledge if he had come from a merchant or a family with means. The average peasant, I would say learnt his religion from the Ulema who were present in mosques and from Sufi Khanaqahs, if one was around him, and they would be taught religion as well.
I would think that prostitution would be frowned upon at least among the peasants, but it would have been a livelihood, though not a generally accepted one, but once again homosexuality would fall under whatever rubric that the Ulema or Sufi himself believed in. Certainly the concept of Sin would have been taught as well.
For the presence of the Ulema as a political class I suggest History of the Khiljis AD 1290-1320 by Kishori Saran Lal, Life and Condition of the People of Hindustan by K. M. Ashraf, the Venture of Islam series by Marshall G.S. Hodgson, Religion and Politics in Saljuqid Iran by Omid Safi.
For General topics references Islam: The Religion and People by Bernard Lewis and Buntzie Ellis Churchill and Before Homosexuality in the Arab-Islamic world, 1500-1800 by Khalid El-Rouayheb should help more with the topic.