Presenting oneself neatly and speaking confidently are not wrong in themselves. The moral problem begins when a person falsely claims a distinction, qualification, or achievement so that others will be misled.
Example 1: Using someone else’s qualification as one’s own in a job application.
Example 2: Claiming to have given a large donation that was never given.
Example 3: Describing one’s genuine level of experience, even if it attracts less praise.
بِمَا لَمْ يُعْطَ distinguishes gratitude for what one truly has from inventing a status one has not received.