In the chapter 7 of book three in Lord of the Rings titled "Helm's Deep", the scout says the following.
‘It is very great,’ said the scout. ‘He that flies counts every foeman twice, yet I have spoken to stouthearted men, and I do not doubt that the main strength of the enemy is many times as great as all that we have here.
Who is "He that flies"? I also can't understand the meaning of the whole passage, so please explain it all.