Read this: Jefferson's opponents said his position was the destruction and the governmental rejection of Christianity, but this was a caricature. In setting up the University of Virginia, Jefferson encouraged all the separate sects to have preachers of their own, though there was a constitutional ban on the State supporting a Professorship of Divinity, arising from his own Virginia Statute for Religious Freedom. Some have argued that this arrangement was "fully compatible with Jefferson's views on the separation of church and state;" however, others point to Jefferson's support for a scheme in which students at the University would attend religious worship each morning as evidence that his views were not consistent with strict separation. Still other scholars, such as Mark David Hall, attempt to sidestep the whole issue by arguing that American jurisprudence focuses too narrowly on this one Jeffersonian letter while failing to account for other relevant history
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): How was the state banned from supporting a Professorship of Divinity?
Virginia Statute for Religious Freedom