The Prophet (SAW) said: Whoever has pride in his heart equal to the weight of a mustard seed shall not enter paradise. Someone said ' A person likes to wear beautiful clothes and fine shoes'. he replied 'Allah is beautiful and likes beauty. Pride means rejecting the truth and looking down on other people.
The Prophet (SAW) said: Eat, drink, give charity and wear (nice) clothes, (as long as you do so) without arrogance and extravagence. Allah loves that His blessings to be seen on His servant.
Ahmad, Ibn Majah
The Prophet (SAW) said: Indeed, Allah has saved you from the ignorant practices (of the days before Islam) and the bad habits of boasting about ancestors. A person is only a pious believer or a miserable sinner. All people are the children of Adam, and Adam was created from dust.
Ahmad, Abu Dawud
The Prophet (SAW) said: Shall I not tell you who the inhabitants of Hell are? They are the people who are stuck up, arrogant and stubborn.