εἰ βαθὺ τὸ τμῆμά

From LSJ

τοῦ δὲ πολέμου οἱ καιροὶ οὐ μενετοί → in war, opportunities won't wait | the chances of war will not wait (Thucydides 1.142.2)

Source

Greek > English (Woodhouse)

if the cut be deep