Love
The repeated sentence praising God for His love is an obvious feature of this Psalm. Your translation might say “faithful love” or “steadfast love.” The idea is that God loves in a way that cannot fail. The writer of the Psalm is thanking God for what He has done and recognizes it was all motivated by God’s love for His people.
Repeating a phrase to focus our attention on God can be a powerful practice. Today, when your thoughts go in directions that are not helpful, refocus your attention on God by saying in your mind, “His faithful love endures forever.”