However, there was a separation between those that wielded authority in politics and religious leaders, when talking historically and what was practiced. Historically speaking, it had been rare for political power to lie solely in the hands of the religious authorities. However, one must take into account that sharia law was not purely for religious matters, but had jurisdiction in all walks of life. However, there is a saying by the Prophet Muhammad, compiled in one of the most authentic books of Hadith, that dealt with this issue and seems to actually support secularism to some degree.
The story said that the prophet Muhammad at some point was opposed to practices of artificially pollinating palm trees. However, he saw later that without the artificial pollination, the trees gave almost not fruit the following year. The prophet Muhammad went on to admit his mistake and followed by stating that whatever he said about religion was clearly his expertise but, relating to secular affairs then perhaps other men know best. This saying has several different interpretations. One must remember that Islam is a very practical religion and that one of the aspects about Islam that many Muslims and converts enjoy is its common sense, its practicality in everyday life. Islam then, makes a distinction between religious knowledge and scientific knowledge, or knowledge of the physical world. While the Qur'an and the Hadith are considered the maximum source of religious knowledge and the revelation of God to His people, the Qur'an also urges Muslims to investigate and observe how the world around them works and to gain as much knowledge as they can about the world around them. In this sense, Islam differs from many other religions that have actively been at odds with many aspects of scientific progress. It is then no coincidence that the great scientific discoveries of the centuries leading up to the Renaissance were made in the Muslim world.
So, most Muslims will agree that the divine is strictly for religious affairs and ethical dilemmas. When it comes to science and the physical workings of the world around is, it is human perspective and knowledge that matters. In that sense, while Islam is clearly opposed to secularism in its meaning of a separation between religion and state, there is a clear sense of separation between religion and science, something that could be considered Islamic secularism.