Pride, with its consequences, remains a great sin opposing the purpose for which Allaah (subhaanahu wa ta’aala) created His creation, just as the greatest sin, polytheism. Allaah (subhaanahu wa ta’aala) created His creation and revealed His Book in order that complete obedience be devoted to Him, alone. Therefore, He (subhaanahu wa ta’aala) forbade the entry into Paradise for polytheists and any of those who have the weight of a mustard seed of pride in their hearts.
 

Ibn Qayyim Al-Jawziyyah