It is narrated from Sayyiduna Ibn Mas'ud (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever says three times: 'Astaghfirullahal-ladhi la ilaha illa huwal-Hayyul-Qayyumu wa atubu ilayh' (I seek forgiveness from Allah, besides whom there is no god, the Ever-Living, the Sustainer of all, and I turn to Him in repentance), his sins are forgiven, even if he had fled from the battlefield." This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it.