Musnad Ahmad 1017:43

Waki’ narrated to us, Sufyan narrated to us, from ‘Alqamah ibn Marthad, from Sulayman ibn Buraydah, from his father, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The sanctity of the wives of the mujahideen for those who stay behind is like the sanctity of their mothers. There is no man among those who stay behind who succeeds a man among the mujahideen in his family and betrays him regarding them, except that he will be made to stand for him on the Day of Resurrection, and he will take from his good deeds whatever he wishes. So what do you think?"