Taking credit for things you don't control.
For example, do you have a high IQ? If so, you were born with that and shouldn't look down your nose at dimwits (if you think this word is harsh Google it-I chose it over moron). Have talents or good looks? There's no cause to be proud of that, you had nothing to do with it.
A woman asked the pastor for counseling. She said it was her besetting sin that she has noticed she is the most beautiful woman in the church, and can't help but notice that no other ladies can even hold a candle to her beauty. "What can I do about this sin?" He replied, "Oh dear lady, that's not a sin...just a mistake!"
Charles Spurgeon said, "Be not proud of race, face, place, or grace." It's ok to be thankful for advantages you have, but not prideful.
Obadiah 1:3 (KJV) “The pride of your heart has deceived you, you who live in the clefts of the rocks and make your home on the heights, you who say to yourself, ‘Who can bring me down to the ground?”