Integrity is being who we say we are. It's in the Bible, Psalm 25:21, NIV. "May integrity and uprightness protect me, because my hope is in You."
One of the most difficult tests of integrity is wealth. It's in the Bible, Luke 16:10-11, NIV. "Whoever can be trusted with very little can also be trusted with much, and whoever is dishonest with very little will also be dishonest with much. So if you have not been trustworthy in handling worldly wealth, who will trust you with true riches?"