Albert Barnes Commentary Psalms 146:6

"Who made heaven and earth, The sea, and all that in them is; Who keepeth truth for ever;" — Psalms 146:6 (ASV)

Which made heaven and earth ... — Who is the true God, the Creator of all things. Happy is he who can address the God who called all this wondrous universe into being, and who sustains all by his power, as his God.

Which keepeth truth for ever — Who is always true to his promises. In this verse, two reasons are given why the condition of the people of God would be a happy one:

1. That Yahweh is the true God, the Creator of all things, and, therefore, able to protect and provide for them.
2. That he is faithful, and may always be relied on.

Idol-gods have no power, and any reliance placed on them is in vain. People are often false and cannot be trusted, but Yahweh has infinite power, and every promise that he makes will be fulfilled; all that he says is eternally and unchangeably true. The reasons for trusting in him, or the reasons why those who trust in him are happy, are further stated in the following verses.