The commercial character of the opening figures of ch. lv. arrests the attention. We saw that Babylon was the centre of the world's trade, and that it was in Babylon that the Jews first formed those mercantile habits, which have become, next to religion, or in place of religion, their national character. Born to be priests, the Jews drew down their splendid powers of attention, pertinacity and imagination from God upon the world, till they equally appear to have been born traders. They laboured and prospered exceedingly, gathering property and settling in comfort. They drank of the streams of Babylon, no longer made bitter by their tears, and ceased to think upon Zion. But, of all men, exiles can least forget that there is that which money can never buy. Money and his work can do much for the banished man,--feed him, clothe him, even make for him a kind of second home, and in time, by the payment of taxes, a kind of second citizenship; but they can never bring him to the true climate of his heart, nor win for him his real life. And of all exiles the Jew, however free and prosperous in his banishment he might be, was least able to find his life among the good things--the water, the wine and the milk--of a strange country. For home to Israel meant not only home, but duty, righteousness and God.[253] God had created the heart of this people to hunger for His word, and in His word they could alone find the _fatness of their soul_. Success and comfort shall never satisfy the soul which God has created for obedience. The simplicity of the obedience that is here asked from Israel, the emphasis that is laid upon mere obedience as ringing in full satisfaction, is impressive: _hearken diligently, and eat that which is good; incline your ear and come unto Me, hear and your soul shall live_. It suggests the number of plausible reasons, which may be offered for every worldly and material life, and to which there is no answer save the call of God's own voice to obedience and surrender. To obedience God then promises influence. In place of being a mere trafficker with the nations, or, at best, their purveyor and money-lender, the Jew, if he obeys God, shall be the priest and prophet of the peoples. This is illustrated in vv. 4_b_-6, the only hard passage in the chapter. God will make His people like David; whether the historical David or the ideal David described by Jeremiah and Ezekiel is uncertain.[254] God will conclude an _everlasting covenant_ with them, equivalent to the _sure favours_ showered on him. As God set him for a _witness_ (that is, a prophet) to _the peoples_, a _prince and a leader to the peoples_, so (in phrases that recall some used by David of himself in the eighteenth Psalm) shall they as prophets and kings influence strange nations--_calling a nation thou knowest not, and nations that have not known thee shall run unto thee_. The effect of the unconscious influence, which obedience to God, and surrender