Matthew Henry on Psalms 135:1-4

The subject-matter of praise, is the blessings of grace flowing from the everlasting love of God. The name of God as a covenant God and Father in Christ, blessing us with all spiritual blessings in him, is to be loved and praised. The Lord chose a people to himself, that they might be unto him for a name and a praise. If they do not praise him for this distinguishing favour, they are the most unworthy and ungrateful of all people.