The word translated ‘heathen’ is the word also rendered ‘nations’ and ‘Gentiles’, but here the sense demands a word which indicates unbelieving people, so ‘heathen’ works well. ‘For the day of the LORD is near upon all the heathen’ – the Day of Judgment.
The picture applies today. Before we are converted, we do strut about this world as though we own the place, with no time for God and no interest in him. But that will bring us into judgment if we never repent and if we never turn to him.
Who's interested in the Edomites today? They are inconsequential, irrelevant, and so with us. If only we could see it this way: all I think, all I achieve in this life, my family perhaps, my place of business perhaps, all that's so important to me, all that I've accomplished, viewed eternally, it is immaterial; it’s inconsequential. It doesn't count. In fifty years nobody will remember it, in one hundred years nobody will know anything about it. When the world is ended and the eternal glory comes in and all the unsaved are thrust away from the presence of God into everlasting punishment, all that you have done, all you have achieved: it won't even be written down. In heaven there will never be a class held anywhere in which they study what worldly people have achieved. It will be as though they had never been.