Jeremiah is the prophet of Lamentations, speaking to his people on the eve of the Babylonian Captivity, when they would lose their nation, their capitol city, and their temple, and be taken into exile to Babylon the Great, the ascendant world empire of that time. This exile was a fulfillment of the great curse in Deuteronomy 15, when God set before His people a great blessing if they remained faithful to Him, and a great curse if they did not. It is hundreds of years later, hundreds of years of the Israelites repeatedly choosing other gods to trust in, and there is now no longer any reprieve.
Yet here on the eve of disaster, God sends his people comfort. Even though they will lose their own land, and become strangers in a foreign land, yet they are to seek there a full life, not a life of sulking or violent resistance. They are to build homes there, plant gardens, marry and raise children, and, in sum, prosper. Furthermore, they are not to seek to undermine or terrorize their Babylonian captors, but are to seek the good of that city full of pride and idols.
The Israelites know what is good; they have been taught by God for hundreds of years. They know it includes justice for all and especially for the weak and disenfranchised and for the foreigner among them. They know it involves trusting in God rather than in powerful men or alliances with powerful nations. They know it involves faithfulness to wives, husbands, and children. They know it requires the teaching to one’s children all these things so that these truths will not be lost beneath the press of generations, but will continue on the earth. They know how to prosper.
In the book of Daniel we see this command to live well among the Babylonians, and to seek their good, carried out by Daniel and his friends. They learn all the lore of the Babylonians, become experts in their ways, but live in such a manner as to show a better way. Daniel is a faithful prime minister to Nebuchadnezzar and his successor, giving them godly advice, and in his living, in his continued open worship not of their gods but of the true God, he brings them to give glory to God and, no doubt, makes Babylon a more just nation than it would have otherwise been.
Today the Church sojourns in a land not its own, which is similar to Babylon in many ways, and which may in fact be the spiritual Babylon the Great depicted in the Revelation to John. We should likewise seek her true Good, and live within her as just and honest and merciful exiles awaiting our true home while making the land of our exile as good as she will allow. This Babylon will fall as surely and as completely as her namesake of old did, in fact, more completely and finally. But while we live within her, let us seek to do good to all persons and live out the Way that we have been shown.