Charles Spurgeon Commentary 2 Chronicles 11:1-4

"And when Rehoboam was come to Jerusalem, he assembled the house of Judah and Benjamin, a hundred and fourscore thousand chosen men, that were warriors, to fight against Israel, to bring the kingdom again to Rehoboam. But the word of Jehovah came to Shemaiah the man of God, saying, Speak unto Rehoboam the son of Solomon, king of Judah, and to all Israel in Judah and Benjamin, saying, Thus saith Jehovah, Ye shall not go up, nor fight against your brethren: return every man to his house; for this thing is of me. So they hearkened unto the words of Jehovah, and returned from going against Jeroboam." — 2 Chronicles 11:1-4 (ASV)

And when Rehoboam was come to Jerusalem, he gathered of the house of Judah and Benjamin an hundred and fourscore thousand chosen men, which were warriors, to fight against Israel, that he might bring the kingdom again to Rehoboam. But the word of the LORD came to Shemaiah the man of God, saying, Speak unto Rehoboam the son of Solomon, king of Judah, and to all Israel in Judah and Benjamin, saying, Thus saith the LORD, Ye shall not go up, nor fight against your brethren: return every man to his house: for this thing is done of me. And they obeyed the words of the LORD, and returned from going against Jeroboam.

So far, so good. There was some degree of the fear of God in the minds of men when, at the bidding of a single prophet, a king would disband his troops, and cease from war.