Musnad Ahmad 939:8

'Abd al-Samad narrated to us, Harb narrated to us, Yahya narrated to us, Abu Salamah narrated to me, Busr ibn Sa'id narrated to me, Zayd ibn Khalid al-Juhani narrated to me, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever equips a warrior, he has indeed fought. And whoever looks after a warrior in his family with goodness, he has indeed fought."