We often think of adornment as outward display – jewelry, nice clothes, perfect hair. But the Bible points to a beauty that starts much deeper.
Peter isn't saying outward beauty is wrong! The point is about where true, lasting beauty originates. He contrasts the world's view with God's view. The holy women of old didn't adorn themselves primarily with external things. Their true adornment was an internal reality – a hope firmly placed in God, which naturally led to a beautiful character and behavior, specifically, submitting to their husbands out of reverence for God.