Nahum begins his prophecy by discussing the holiness, omnipotence, and righteousness of God. As a jealous God (zealous for righteousness), He will protect His holy name, but the Assyrians in their pride had mocked Him, and because they were enemies of His people, they were also His enemies. They conspired evil against the Lord (1:9,11). Nahum describes God's furious vengeance, which will be irresistible (1:2, 6, 9). The prophet, however, does not want his readers to think that God is quick-tempered, like man, so he explains that "the Lord is slow to anger" (1:3). The actual fulfillment of this prophecy was not to happen for many years, but Nahum asserts that it would indeed come, for God's justice demands that He punish their sin.
Nahum wants the people to understand that God is not only a God of wrath and judgment, but He is good and a tower of strength to those who trust in Him. The people of Nineveh, however, did not put their trust in the Lord. They rather trusted in their highly fortified city. A century and a half earlier, under the ministry of Jonah, the people of Nineveh had repented of their wickedness and served God, but now they had forgotten God and once again became the most wicked, cruel, and oppressive nation.
With an amazing prophecy, Nahum predicts that God would cause an "overflowing flood" and bring Nineveh to ruin (1:8). Historical records show that the fall of Nineveh came because the Tigris River suddenly overflowed its banks ("the gates of the rivers are opened"), and this caused the walls of the city to collapse and the foundations of the palace to fall apart (2:6). At the same time, the armies of the Medes and Babylonians came against Nineveh and entered through the breach in the wall. Nineveh's walls were very high and thick, so her many citizens thought they were safe, but with the Lord's intervention, the invading army would overtake the city.
Nahum gives an example of the wickedness of Nineveh. They had defied the God of Israel and conspired against Him by subjugating His people. The many inhabitants of Nineveh thought they were invincible, but the Lord would prevail against them. With the fall of Nineveh and their king, the Lord would break the Assyrian yoke off the necks of His people, and that nation would pass away. Although the Lord had used Assyria to chastise His people, this source of chastisement would end (1:12-13; cf. Isa. 10:5-12). The "good tidings" that would be shouted from the hilltops of Judah would be about the fall of Nineveh. At that time the rituals at the Temple in Jerusalem would be able to return to normal. This is the "excellence of Jacob" which shall be restored (2:2). The Assyrians would no longer go through Judah to collect taxes and oppress the people ("empty them out and ruin their vine branches", 2:2), for Nineveh would be "utterly cut off" (1:15). With an ironic twist, Nahum calls upon the Ninevites to prepare themselves for battle (2:1), for the great army garbed in red (Medo- Babylonian; cf. Ezek. 23:14) will come against them, and they will race through the streets of the city (2:3-4). The king will call upon his select guard (his "worthies") to defend the city, but they would "stumble in their walk" (2:5). One ancient historian tells that they were all drunk at the time the Babylonian army broke through the collapsed wall. Rather than helping to defend their city, the inhabitants would flee in fear, but they would be caught and led away captive. The very things the Ninevites had done to other peoples would be done to them. All the vast amounts of spoil they had taken from other cities would be taken from her, and Nineveh would be made desolate. The city that was once as feared as a dwelling of lions would disappear off the face of the earth. For centuries people walked over the tel of Nineveh, not even aware that the ancient and once beautiful "pool of water" was buried beneath their feet (2:8a, 11-12). Why did this happen to Nineveh? God Himself was against her because of her sinfulness against Him. Any nation that persists in wickedness is sure to face the judgment of the Lord (Amos 9:8).