Charles Ellicott Commentary Psalms 138:2

"I will worship toward thy holy temple, And give thanks unto thy name for thy lovingkindness and for thy truth: For thou hast magnified thy word above all thy name." — Psalms 138:2 (ASV)

Notice that “loving-kindness” and “truth” are joined as inseparable attributes of Jehovah in His relationship to the chosen race.

For you have magnified— that is, the promise made for help and deliverance has been fulfilled, and more than fulfilled. The psalmist often speaks of Jehovah’s name, or reputation, or honor being at stake. Here the poet can say that the praise won is even beyond what might have been expected. It is true this would have been expressed more in accordance with our expectation by “You have magnified Your Name above Your promise;” but compare Psalms 48:10 for a similar thought, and for the language compare Tennyson’s:

“I am become a name.”

The Septuagint and Vulgate felt the difficulty too great, and render “Your holy one,” instead of “Your word.”