Jundub bin Abdullah (May Allah be pleased with him) reported:
Messenger of Allah (ﷺ) said, "He who performs the Fajr (dawn) prayer comes under the Protection of Allah, so beware lest Allah questions you about what you owe Him. For if He questions anyone of you and he falls short of fulfilling the duty which he owes Him, He will requite and then throw upon his face into the Hell- fire".[Muslim].
Arabic/English book reference: Book 1, Hadith 389