Open theism is a libertarian view of free will claiming that God’s omniscience does not extend to knowing the actual choices of free human agents. It is a theory of “dynamic omniscience”.
The first known post-biblical Christian writings advocating concepts similar to open theism with regard to the issue of foreknowledge are found in the writings of Calcidius, a 4th-century interpreter of Plato. It was affirmed in the 16th century by Socinus, and in the early 18th century by Samuel Fancourt and by Andrew Ramsay (an important figure in Methodism). In the 19th century several theologians wrote in defense of this idea, including Isaak August Dorner, Gustav Fechner, Otto Pfleiderer, Jules Lequier, Adam Clarke, Billy Hibbard, Joel Hayes, T.W. Brents, and Lorenzo D. McCabe. Contributions to this defense increased as the century drew to a close.
Outside of Christianity, Cicero expressed similar views according to the Information Philosopher:
If there is free will, all things do not happen according to fate; if all things do not happen according to fate, there is not a certain order of causes; and if there is not a certain order of causes, neither is there a certain order of things foreknown by God.
I am looking for references, such as the Cicero quote above, of other theistic positions supporting ideas similar to open theism besides those expressed within Christianity.