John Calvin Commentary Psalms 146:10

"Jehovah will reign for ever, Thy God, O Zion, unto all generations. Praise ye Jehovah." — Psalms 146:10 (ASV)

Jehovah shall reign, and so forth. He directs his discourse to the Church to more effectively persuade all God’s people that they will truly find Him to be as He had just been described. When he says that God is king forever, we must also remember the purpose for which He reigns—understanding its definition from the preceding description.

It follows that, whether living or dying, we will be safe under the keeping of a king who reigns specifically for our salvation. If he had said no more than that Jehovah reigned forever, we might have readily objected, considering the distance between us and His inconceivable greatness. Therefore, He states in explicit terms His being bound by a sacred covenant to His chosen people.