Musnad Ahmad 8:28

Abu al-Yaman narrated to us, Abu Bakr ibn Abdullah narrated to us, from Rashid ibn Sa’d, from Sa’d ibn Abi Waqqas, who said: The Messenger of Allah, peace and blessings of Allah be upon him, was asked about this verse: "He is the One capable of sending upon you a punishment from above you or from beneath your feet" [Al-An’am: 65]. The Messenger of Allah, peace and blessings of Allah be upon him, said: "As for it, it is going to happen, and its interpretation has not come yet."