Narrated Zayd, the client of the Prophet: The Prophet ﷺ said: If anyone says: "I ask pardon of Allah than Whom there is no deity, the Living, the eternal, and I turn to Him in repentance, " he will be pardoned, even if he has fled in time of battle.
Hadith ReferenceSunan Abi Dawud / Prayer (Kitab Al-Salat): Detailed Injunctions about Witr / Hadith: 1517
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:حسن, مشكوة المصابيح (2353), وللحديث شاھد حسن عند الحاكم (1/511، 2/117، 118)