As David records this portion of God's word we should remember he is the King and as the King he would have access to the best of his day. However as he pens down these word we find there is no mention of his material possessions as being good or being pleasant.
Notice what David writes:
Psalms 133:1.... Behold, how good and how pleasant it is for brethren to dwell together in unity!
The word good has the meaning of "beneficial".
The word pleasant has the meaning of "beauty".
The word dwell has the meaning of "a relationship as in marriage".
David recording words for eternity writes of the benefit, the beauty, and the relationship found only in unity of the believers. Just think... if David is this excited in seeing God's people in unity think how this must please our Lord.
May we all, as believers, strive to dwell together in unity.