Musnad Ahmad 1015:3

'Abd al-Malik ibn 'Amr narrated to us, Zuhayr—meaning Ibn Muhammad—narrated to us, from 'Abd Allah ibn Muhammad ibn 'Aqil, from 'Ata' ibn Yasar, from Abu Malik al-Ash'ari, from the Prophet, peace and blessings of Allah be upon him, who said: "The greatest of *ghulul* (unlawful taking of spoils or property) in the sight of Allah is a cubit of land. You find two men who are neighbors on a piece of land or in a house, and one of them cuts off a cubit from his companion's share. If he cuts it off, he will be encircled by it from seven earths until the Day of Resurrection."