Louis Berkhof, in his Systematic Theology (p. 165), pointed out that “Over against the doctrines of fate and chance, [Augustine] stressed the fact that all things are preserved and governed by the sovereign, wise, and beneficent will of God.”
In his Consolation of Philosophy (Book 5), Boethius wrote (correctly, I believe): “If chance be defined as a result produced by random movement without any link of causal connection, I roundly affirm that there is no such thing as chance at all, and consider the word to be altogether without meaning, except as a symbol of the thing designated. What place can be left for random action, when God constraineth all things to order?”
Condemned by Augustine, Fortuna is not a concept compatible with Christianity.
And so, “Whenever something is done for the sake of a particular end, and for certain reasons some other result than that designed ensues, this is called chance; for instance, if a man is digging the earth for tillage, and finds a mass of buried gold. Now, such a find is regarded as accidental; yet it is not ‘ex nihilo,’ for it has its proper causes, the unforeseen and unexpected concurrence of which has brought the chance about. For had not the cultivator been digging, had not the man who hid the money buried it in that precise spot, the gold would not have been found. These, then, are the reasons why the find is a chance one, in that it results from causes which met together and concurred, not from any intention on the part of the discoverer. Since neither he who buried the gold nor he who worked in the field intended that the money should be found, but, as I said, it happened by coincidence that one dug where the other buried the treasure. We may, then, define chance as being an unexpected result flowing from a concurrence of causes where the several factors had some definite end. But the meeting and concurrence of these causes arises from that inevitable chain of order which, flowing from the fountain-head of Providence, disposes all things in their due time and place.” – Boethius, Consolation of Philosophy (Book 5)
Parable of the Hidden Treasure by Rembrandt
There are indeed certain physical phenomena, such as the radioactive decay of a specific atom, that have no known immediate cause, but this is not the same as being uncaused. In particular, causal “hidden variable” models of radioactive decay are possible in theory, although they would be nonlocal models. And of course, from a Christian point of view, each atomic decay is caused by God. However, at our present state of understanding, we say that individual atoms behave “randomly,” in that we simply do not know what an individual atom will do, although we are aware of laws which large collections of atoms follow. Such scientific concepts are, of course, fully compatible with Christian theology, in spite of occasional suggestions to the contrary.