Albert Barnes Commentary Psalms 115:1

"Not unto us, O Jehovah, not unto us, But unto thy name give glory, For thy lovingkindness, and for thy truth`s sake." — Psalms 115:1 (ASV)

Not unto us, O Lord, not unto us, but unto your name give glory — This apparently abrupt commencement of the psalm was undoubtedly in reference to some circumstances. These would have been well understood when the psalm was composed, but they cannot be definitively ascertained now.

It seems to have been in view of some existing troubles. The language simultaneously expresses a hope for divine interposition and a conviction that the praise for such an interposition would belong entirely to God. The phrase "give glory" means to give all the honor and praise. See the notes at Psalms 29:1-2.

For your mercy — The mercy or the favor which we seek and look for—your gracious help in the time of trouble.

And for your truth’s sake — Your faithfulness to your promises; your faithfulness to your people. The psalmist anticipated this manifestation of faithfulness with confidence; he felt that all the praise for such an anticipated interposition would belong to God.