1 Peter 3:3-4

Your adornment must not be merely external—with interweaving and elaborate knotting of the hair, and wearing gold jewelry, or [being superficially preoccupied with] dressing in expensive clothes; but let it be [the inner beauty of] the hidden person of the heart, with the imperishable quality and unfading charm of a gentle and peaceful spirit, [one that is calm and self-controlled, not overanxious, but serene and spiritually mature] which is very precious in the sight of God.