5, 6. Explanation of the symbols:
      Jerusalem--not the mere city, but the people of Israel generally, of which it was the center and representative.
      in . . . midst--Jerusalem is regarded in God's point of view as center of the whole earth, designed to radiate the true light over the nations in all directions. Compare Margin ("navel"), Eze 38:12; Ps 48:2; Jer 3:17. No center in the ancient heathen world could have been selected more fitted than Canaan to be a vantage ground, whence the people of God might have acted with success upon the heathenism of the world. It lay midway between the oldest and most civilized states, Egypt and Ethiopia on one side, and Babylon, Nineveh, and India on the other, and afterwards Persia, Greece, and Rome. The Phœnician mariners were close by, through whom they might have transmitted the true religion to the remotest lands; and all around the Ishmaelites, the great inland traders in South Asia and North Africa. Israel was thus placed, not for its own selfish good, but to be the spiritual benefactor of the whole world. Compare Ps 67:1-7 throughout. Failing in this, and falling into idolatry, its guilt was far worse than that of the heathen; not that Israel literally went beyond the heathen in abominable idolatries. But "corruptio optimi pessima"; the perversion of that which in itself is the best is worse than the perversion of that which is less perfect: is in fact the worst of all kinds of perversion. Therefore their punishment was the severest. So the position of the Christian professing Church now, if it be not a light to the heathen world, its condemnation will be sorer than theirs (Mt 5:13; 11:21-24; Heb 10:28, 29).

JFB.