Jundub bin Abdullah (RadiyAllahu anhu) reported: Messenger of Allah (Sallellahu alaihi wa sallam) said, "When anyone offers the Fajr (dawn) prayer, in congregation, he is in the Protection of Allah. So let not Allah call him to account, withdrawing, in any respect, His Protection. Because, He will get hold of him and throw him down on his face in the Hell-fire.''
This Hadith tells us that the Fajr prayer is in the nature of an agreement between Allah and His slave (Muslim). It tells us that he would not all day long depart from the way of Allah as he has not done by performing his Fajr prayer. He will not only perform all the other prescribed prayers but would also do nothing which will displease Allah. A Muslim who does not care to adhere to this agreement, and thereby shows disobedience of Allah, will be answerable to Him for it on the Day of Resurrection.