It is narrated from Sayyiduna Abu Ayyub (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "There is no one who does not associate anything with Allah, establishes the prayer, gives zakah, fasts Ramadan and avoids the major sins, except that Paradise becomes obligatory for him." The people asked: What are the major sins? He (peace and blessings be upon him) said: "Associating partners with Allah, killing a Muslim soul, and fleeing from the battlefield on the day of the advance."
Hadith Referenceالمعجم الكبير للطبراني / باب الخاء / 3870