And they shall be changed - Not destroyed ultimately, or annihilated. They shall be changed and renewed.
But thou art the same - These words can be said of no being but God; all others are changeable or perishable, because temporal; only that which is eternal can continue essentially, and, speaking after the manner of men, formally the same.
Thy years shall not fail - There is in the Divine duration no circle to be run, no space to be measured, no time to be reckoned.