He sendeth forth his commandment upon earth - That is, with reference to the productions of the earth; to the changes which occur; to the seasons; to snow, frost, ice, cold, heat, wind; and he is universally and immediately obeyed. Nature everywhere yields a ready acquiescence to his will.
His word runneth very swiftly - As if it hastened to obey him. There is no delay. Compare the notes at Psalms 33:9 : “He spake, and it was done; he commanded, and it stood fast.” Snow, and frost, and ice, and cold, and heat, and wind, are entirely obedient to him. There is no reluctance in obeying him; there is no delay.