Sunan at-Tirmithiy كتاب تفسير القرآن باب ومن سورة الأنفال
The Messenger of God, peace and blessings of God be upon him, said, "God sent down to me two guarantees of safety [against His immediate torment] for my nation; 'But Allah would not punish them while you, [O Muhammad], are among them, and Allah would not punish them while they seek forgiveness' (8 [al-Anfāl]: 33). When I pass away, I leave with them [the act of] seeking forgiveness, until the Day of Resurrection." Click on ḥadīth to read more