Note to Macbeth, Act 1, Scene 3, lines 147-148: "Come what come may, / Time and the hour runs through the roughest day"

Act 1, Scene 3, line 147.
I'm not sure what Macbeth means here. He has just said that "chance" may crown him without him doing anything, so he may mean "Whatever happens, time always goes forward, so I'll just wait and see how things turn out." However, the word "hour" suggests "opportunity" or "decisive moment," so maybe he's also thinking that "Whatever happens, seizing a present opportunity will enable me to override any obstacles."