“Tell Rehoboam son of Solomon king of Judah, all the house of Judah and Benjamin, and the rest of the people
Shemaiah is told to speak to Rehoboam, to Judah and Benjamin, and to the rest of the people.
It widens the audience of God's command beyond the king alone.
20When all Israel heard that Jeroboam had returned, they summoned him to the assembly and made him king over all Israel. Only the tribe of Judah followed the house of David. 21And when Rehoboam arrived in Jerusalem, he mobilized the whole house of Judah and the tribe of Benjamin — 180,000 chosen warriors — to fight against the house of Israel and restore the kingdom to Rehoboam son of Solomon. 22But the word of God came to Shemaiah the man of God: 23“Tell Rehoboam son of Solomon king of Judah, all the house of Judah and Benjamin, and the rest of the people 24that this is what the LORD says: ‘You are not to go up and fight against your brothers, the Israelites. Each of you must return home, for this is My doing.’”