"For the day of the LORD is near upon all the heathen: as thou hast done, it shall be done unto thee: thy reward shall return upon thine own head." (Obadiah 15)
The book of Obadiah was possibly the earliest of the prophetic books of the Old Testament and is certainly the shortest, with its single chapter. Its theme is God's coming judgment on the Edomite nation, not only because of their general wickedness, but particularly because of their abusive treatment of their Israelite relatives (Jacob's brother Esau was the father of the Edomites).
The prophecy of Obadiah contains (in our text) the first mention (chronologically) of the coming "day of the LORD." Although it appears at first to focus especially on the Edomites, it is really looking far ahead to the end times, when the judgments of that day will be "upon all the heathen." There have been many precursive and partial fulfillments of this prophecy, as nation after nation has been brought down throughout history under God's judgmental hand. Edom, in particular, has long since vanished as a nation.
There is a great day coming, however (actually a period of time), called in the Bible "the day of the Lord" (also "that day," "the great day of His wrath," and other such terms), when all the heathen (that is, the "Gentile nations," including the U.S.) will be judged by the God who created them, who died to redeem them, and who has been repudiated by them. "And out of his mouth goeth a sharp sword, that with it he should smite the nations: . . . and he treadeth the winepress of the fierceness and wrath of Almighty God" (Revelation 19:15). Our own heathen nation has been spared thus far because of our biblical foundations, our care for God's people, Israel, and our missionary efforts, but these are fast disappearing, and our time, like that of Edom, will surely come. HMM