Isaiah 40:3 - Ellicott's Commentary On The Whole Bible

The voice of him that crieth... — The laws of Hebrew parallelism require a different punctuation: A voice of one crying, In the wilderness, prepare ye ... The passage is memorable as having been deliberately taken by the Baptist as defining his own mission (John 1:23). As here the herald is not named, so he was content to efface himself — to be a voice or nothing. The image is drawn from the march of Eastern kings, who often boast, as in the Assyrian inscriptions of Sennacherib and Assurbanipal (Records of the Past, i. 95, vii. 64), of the roads they have made in trackless deserts. The wilderness is that which lay between the Euphrates and Judah, the journey of the exiles through it reminding the prophet of the older wanderings in the wilderness of Sin (Psalms 68:7; Judges 5:4). The words are an echo of the earlier thought of Isaiah 35:8. We are left to conjecture to whom the command is addressed: tribes of the desert, angelic ministers, kings and rulers — the very vagueness giving a grand universality. So, again, we are not told whether the “way of Jehovah” is that on which He comes to meet His people, or on which He goes before and guides them. The analogy of the marches of the Exodus makes the latter view the more probable.