After the year was expired. Literally, “in the return of the year” (see 1 Kings 20:22, 26). Among the Hebrews the civil year began with the month Tishri in the fall, although the religious year began with Nisan in the spring. Since the autumn was the “going forth” of the year, the spring would be the “return” (see p. 109). The reference here is to the spring, as proved by the next clause.
When kings go forth. The rulers of Western Asia generally started out on their military campaigns in the spring of the year. The winter was unsuited for fighting because of the cold and the rain. Also the roads at that time were well-nigh impassable and supplies of food were not readily available. The Assyrian annals show that almost invariably the spring of the year was chosen for the armies to conduct their campaigns. With the Assyrians these were annual expeditions.
David sent Joab. Joab had spent the winter, or rainy season, at Jerusalem. As soon as the winter was over, David renewed the conflict. During the previous season a crushing defeat had been inflicted on the Syrians, but the Ammonites still retained their power. When attacked by Joab’s forces they had simply retreated within their city walls, whereupon Joab returned to Jerusalem (ch. 10:14). The Ammonites were mainly responsible for this conflict and had hired the Syrians to help them (ch. 10:6). Hence it was necessary for David to deal with them and thus eliminate the Ammonite threat to the security of Israel.
Without the aid of their Syrian allies, the Ammonites alone were no match for the forces of Israel. Since the Syrians had already been subdued, it was only a question of time until the Ammonites, too, would be reduced to submission. David therefore did not consider it essential that he personally take the field against Ammon, but entrusted the conduct of the war to Joab.
Besieged Rabbah. The Ammonites fell an easy prey to the forces of Israel. The country as a whole was quickly reduced, with the exception of Rabbah, the Ammonite capital (ch. 12:26). When Joab’s men were devastating the countryside of Ammon, many of the people took refuge behind the walls of the capital city. Only a long blockade could bring about its final submission. Surrounding the city, Joab began siege operations. The ultimate doom of the city was certain, for there was no hope of relief from without.
David tarried. While Joab carried on the siege of Rabbah, David remained behind at Jerusalem. He was now at the height of his power. His enemies on all sides had been reduced to submission. Only a remnant of the Ammonites remained, and in a short time they too would be completely subdued. Surrounded by the fruits of victory, receiving honor and acclaim from his own people and from the nations about, his coffers overflowing with the tribute that was pouring in from his defeated foes, David lived a life of ease and contentment. The greatness of his success exposed him to his greatest danger. Satan chose this moment to bring upon the king of Israel a temptation that was to cause him deep humiliation and disgrace. David tragically forgot that there was an enemy greater than men. Feeling himself strong and secure against his earthly enemies, intoxicated by his prosperity and success, while receiving the plaudits of men, Israel’s honored hero and saint was thrown off his guard. Imperceptibly the inner defenses of his soul had weakened, until he yielded to a temptation that transformed him into a shameless sinner.