Go, strengthen thyself ... - That is, "collect troops, raise fortifications, obtain allies ... take all the measures thou canst to increase thy military strength. Be not rash, but consider well every step ... for a great danger is impending."

At the return of the year - i. e., "When the season for military operations again comes round." The wars of the Oriental monarchs at this time, like those of early Rome, were almost always of the nature of annual incursions into the territories of their neighbors, begun in spring and terminating in early autumn. Sustained invasions, lasting over the winter into a second or a third year, are not found until the time of Shalmaneser 2 Kings 17:5; 2 Kings 18:9-10, and do not become common until the Median and Babylonian period.

And the prophet came to the king of Israel,.... The same that came to him before:

and said unto him, go, strengthen thyself; exhorted him to fortify his cities, especially Samaria, and increase his army, that he might be able to oppose the king of Syria:

and mark, and see what thou doest: observe his moral and religious actions, and take heed that he did not offend the Lord by them, as well as make military preparations:

for at the return of the year the king of Syria will come up against thee; about the same time in the next year, at the spring of the year, when kings go out to war, see 2 Samuel 11:1.

After this victory the prophet came to Ahab again, warning him to be upon his guard, for at the turn of the year, i.e., the next spring (see at 2 Samuel 11:1), the Syrian king would make war upon him once more.

And the prophet came to the king of Israel, and said unto him, Go, strengthen thyself, and mark, and see what thou doest: for at the return of the year the king of Syria will come up against thee.

20:22 Mark, and see - Consider what is necessary for thee to do by way of preparation. The enemies of the children of God, are restless in their malice and tho' they may take some breathing time for themselves, they are still breathing out slaughter against the church. It therefore concerns us always to expect our spiritual enemies, and to mark and see what we do.

22-26. the prophet came to the king of Israel, and said-The same prophet who had predicted the victory shortly reappeared, admonishing the king to take every precaution against a renewal of hostilities in the following campaign.

at the return of the year-that is, in spring, when, on the cessation of the rainy season, military campaigns (2Sa 11:1), were anciently begun. It happened as the prophet had forewarned. Brooding over their late disastrous defeat, the attendants of Ben-hadad ascribed the misfortune to two causes-the one arose from the principles of heathenism which led them to consider the gods of Israel as "gods of the hills"; whereas their power to aid the Israelites would be gone if the battle was maintained on the plains. The other cause to which the Syrian courtiers traced their defeat at Samaria, was the presence of the tributary kings, who had probably been the first to take flight; and they recommended "captains to be put in their rooms." Approving of these recommendations, Ben-hadad renewed his invasion of Israel the next spring by the siege of Aphek in the valley of Jezreel (compare 1Sa 29:1, with 1Sa 28:4), not far from En-dor.

20:22-30 Those about Benhadad advised him to change his ground. They take it for granted that it was not Israel, but Israel's gods, that beat them; but they speak very ignorantly of Jehovah. They supposed that Israel had many gods, to whom they ascribed limited power within a certain district; thus vain were the Gentiles in their imaginations concerning God. The greatest wisdom in worldly concerns is often united with the most contemptible folly in the things of God.