133:1 {A Song of degrees. Of David.} Behold, how good and how pleasant it is for brethren to dwell together in unity!
133:2 Like the precious oil upon the head, that ran down upon the beard, upon Aaron's beard, that ran down to the hem of his garments;
133:3 As the dew of Hermon that descendeth on the mountains of Zion; for there hath Jehovah commanded the blessing, life for evermore.
The verse centers on "song", "degrees", "david", "behold", "good", "pleasant", "brethren", and "dwell". It is saying that the verse draws attention to "song" and "degrees", so its meaning should be read from those terms before moving to application.
The local DBY text gives this verse as the immediate unit, so "song" and "degrees" carries the first interpretive weight. In Psalms context, the local focus is worship, trust, the LORD's kingship, and covenant mercy.
A plain takeaway is to answer the verse's own emphasis on "song" and "degrees" with trust shaped by these words, not by a vague optimism outside the passage.