The blessedness of unity among brothers, 1-3.
1 [A Song of Degrees of David.] Behold, how good and how pleasant it is for brothers to dwell together in unity!
2 It is like the precious ointment upon the head that ran down upon the beard, even Aaron's beard, that went down to the skirts of his garment,
3 As the dew of Hermon and as the dew that descended upon the mountains of Zion, for there the LORD commanded the blessing, even life forever.
Matthew Henry Commentary - Psalms, Chapter 133[➚]
John Calvin's Chapter Summary:
A Psalm of thanksgiving for that holy concord which prevailed in the nation, and which the Lord's people are earnestly exhorted to maintain.