Porque ele ainda está se recuperando de sua lesão e sua febre (aquela que fez Denethor pensar que ele estava morto):
Aragorn and Gandalf went now to the Warden of the Houses of Healing, and they counselled him that Faramir and Éowyn should remain there and still be tended with care for many days.
Return of the King Book V Chapter 8: "The Houses of Healing"
Esta cena acontece muito pouco antes (com toda a probabilidade, mais cedo no mesmo dia que) da decisão de marchar sobre Mordor; um capítulo posterior, definido logo após a saída dos exércitos de Minas Tirith, indica que Faramir ainda está lá:
When the Captains were but two days gone, the Lady Éowyn bade the women who tended her to bring her raiment, and she would not be gainsaid, but rose; and when they had clothed her and set her arm in a sling of linen, she went to the Warden of the Houses of Healing.
At a sign from Faramir, the Warden bowed and departed. 'What would you have me do, lady?' said Faramir. 'I also am a prisoner of the healers.' He looked at her, and being a man whom pity deeply stirred, it seemed to him that her loveliness amid her grief would pierce his heart. And she looked at him and saw the grave tenderness in his eyes, and yet knew, for she was bred among men of war, that here was one whom no Rider of the Mark would outmatch in battle.
'What do you wish?' he said again. 'If it lies in my power, I will do it.'
'I would have you command this Warden, and bid him let me go,' she said; but though her words were still proud, her heart faltered, and for the first time she doubted herself. She guessed that this tall man, both stern and gentle, might think her merely wayward, like a child that has not the firmness of mind to go on with a dull task to the end.
'I myself am in the Warden’s keeping,' answered Faramir.
Return of the King Book VI Chapter 5: "The Steward and the King"
A edição estendida do filme inclui uma cena entre Faramir e Éowyn, indicando que ele ficou para trás nas Casas de Cura:
Éowyn: The city has fallen silent. There is no warmth left in the sun. It grows cold.
Faramir: It's just the damp before the first spring rain. I do not believe this darkness will endure.
Return of the King (2003)
Esta cena ocorre imediatamente depois que os Capitães do Oeste são mostrados cavalgando de Minas Tirith.