Give unto the Lord the glory due unto his Name (comp. Psalms 96:8); literally, the glory of his Name; i.e. the glory properly belonging to it. Worship the Lord in the beauty of holiness (comp. Psalms 96:9).
This is generally explained as an exhortation to worship God in beautiful vestments, or with all the accessories of a beautiful ceremonial; but Dr. Alexander rightly questions whether the Beauty inherent in holiness itself is not meant.
The apostle speaks of "the ornament of a meek and quiet spirit" (1 Peter 3:4). And in goodness and holiness of every kind there is a sweetness and grace which may well be called "beauty," seeing that it has a close analogy with the beautiful in external nature and in art.
The Greeks expressed physical beauty and moral perfection by one and the same term— τὸ καλόν.