Commentaries:
The psalmist uses sought out in the sense of "meditated upon" or "thought about." All of us ought to be searching out the works of the Lord—whether it be in history in what He did for His people or in salvation in the redemption of His people and how He supplies all the needs of His people.
John W. Ritenbaugh
The Covenants, Grace, and Law (Part Ten)
It is important to understand when researchers feel this psalm was written: sometime after the Jews returned from their exile in Babylon. In other words, during the time of Nehemiah and Ezra or perhaps shortly thereafter. We should imagine a scribe (someone like Ezra) writing this psalm, extolling how God once again redeemed His people from slavery, brought them back to their land, and supplied their every need.
John W. Ritenbaugh
The Covenants, Grace, and Law (Part Ten)