Musnad Ahmad 456:11

Mu'awiyah ibn 'Amr narrated to us, he said: Ibn Wahb narrated to us, from 'Amr ibn al-Harith, from Bukayr ibn al-Ashajj, from Busr ibn Sa'id, from Zayd ibn Khalid al-Juhani, from the Prophet, peace and blessings of Allah be upon him, who said: "Whoever equips a warrior in the way of Allah, the Almighty and Majestic, has indeed fought. And whoever looks after his family in his absence has indeed fought."