The measure thereof is longer than the earth - The measure of the knowledge of God. The extent of the earth would be one of the longest measures known to the ancients. Yet it is now impossible to ascertain what ideas were attached, in the time of Job, to the extent of the earth - and it is not necessary to know this in order to understand this expression. It is morally certain that the prevailing ideas were very limited, and that a small part of the earth was then known. The general belief seems to have been, that it was a vast plain, surrounded by water - but how supported, and what were its limits, were evidently matters to them unknown. The earliest knowledge which we have of geography, as understood by the Arabs, represents the earth as wholly encompassed by an ocean, like a zone. This was usually characterized as a "Sea of Darkness;" an appellation usually given to the Atlantic; while to the Northern Sea was given the name of "The Sea of Pitchy Darkness." Edrisi imagined the land to be floating in the sea, and only part appearing above, like an egg in a basin of water. If these views prevailed so late as the tenth and eleventh centuries of the Christian era, it is reasonable to conclude that the views of the figure and size of the earth must have been extremely limited in the time of Job. On the ancient views of geography, see the notes at Job 26:7-10, and the maps there, also Murray's Encyclopaedia of Geography, Book I, and Eschenberg's Manual of Classical Literature, by Prof. Fiske, Part I.
And broader than the sea - What was the idea of the breadth of the sea, which was supposed to surround the earth, it is now wholly impossible to determine. Probably there were no ideas on the subject that could be regarded as settled and definite. The ancients had no means of ascertaining this, and they perhaps supposed that the ocean extended to an unlimited extent - or, perhaps, to the far distant place where the sky and the water appeared to meet. At all events it was an illustration then, as it is now, of a vast distance, and is not inappropriately used here to denote the impossibility of fully understanding God. This illustration would be far more striking then than now. We have crossed the ocean; and we do not deem it an impracticable thing to explore the remotest seas. But not so the ancients. They kept close to the shore. They seldom ventured out of sight of land. The enterprise of exploring and crossing the vast ocean, which they supposed encompassed the globe, was regarded by them as wholly impracticable - and equally so they correctly supposed it was to find out God.

The measure thereof is longer than the earth, and broader than the sea. Length is generally ascribed to the earth, and width to the sea; the ends of the earth are used for a great distance, and the sea is called the great and wide sea; see (k) Psalm 72:1; but God and his perfections, particularly his wisdom and understanding, are infinite, Psalm 147:5; and will admit of no dimensions; as his love, so his wisdom, has an height which cannot be reached, a depth that cannot be fathomed, and a length and breadth immeasurable; see Ephesians 3:18; from hence it appears that God is omniscient, omnipresent, and incomprehensible; and since he is to be found in Christ, and in him only, it is in vain for us to seek for him elsewhere: next the sovereignty of God is discoursed of.
(k) "Quid oceano longius inveriri potest", Cicero. Orat. 36.