The Hebrew adjective naveh means beautiful, lovely, fitting, or comely. It describes something that is pleasing and appropriate in its appearance or character. The word appears in Psalm 33:1 describing how praise is fitting for the upright, and in Song of Songs describing the beauty of the beloved.
Beauty in Hebrew thought is not merely aesthetic but moral — what is truly beautiful is what is right, fitting, and in proper order. Naveh connects beauty to appropriateness: praise from the lips of the righteous is beautiful precisely because it is fitting. This reflects the Hebrew understanding that creation was 'very good' — beautifully ordered — and that worship, when offered in spirit and truth, has a rightness and beauty to it. The beauty of holiness (Psalm 29:2) is the supreme expression of naveh.