السَّادِلُ ثَوْبَ خُيَلَائِهِ
You who let the garment of your conceit hang about you!
Al-sādil is one who lets something hang down; khuyalāʾ is self-importance or ostentatious pride. By calling conceit a garment, the speaker makes an inner attitude seem as visible as clothing.
This is a metaphor, not a claim that pride is literally made of cloth. The image exposes the way vanity can shape someone’s outward bearing.