You can't discuss an assertion, but you seem to already know the answer? I wouldn't use the word 'proof' either, but it is arguably a form of logic, to say (I quote again):
Xei: As to what 'causality' actually means, Hume pretty much cracked that one. It doesn't mean anything; it's a fictitious concept based on a baseless extrapolation from experience. A happens, and then B tends to happen after. There is no 'cause' in between; there's no 'therefore' either. It just is. It's a constant conjunction.
You can pick nearly any well received (widely agreed) characteristic of the monotheistic God, and you can support it from the above wisdom.
E.g.
Timeless - if causality doesn't mean anything, time also fails to mean anything. As such, the further statement: "It just is" bears a lot of truth in the existence of eternity. A and B also disappear as fictional events or 'effects' of cause, if cause ceases to exist, further supporting the interplay of time as an artifact of perception and not reality.