"At Jerusalem “he assembled all the house of Judah, with the tribe of Benjamin, an hundred and fourscore thousand chosen men, which were warriors, to fight against the house of Israel, to bring the kingdom again to Rehoboam the son of Solomon. But the word of God came unto Shemaiah the man of God, saying, Speak unto Rehoboam, the son of Solomon, king of Judah, and unto all the house of Judah and Benjamin, and to the remnant of the people, saying, Thus saith the Lord, Ye shall not go up, nor fight against your brethren the children of Israel: return every man to his house; for this thing is from Me. They hearkened therefore to the word of the Lord, and returned to depart, according to the word of the Lord.” Verses 21-24 . PK 91.3"
"Thus saith the Lord, Ye shall not go up, nor fight against your brethren the children of Israel: return every man to his house; for this thing is from me. They hearkened therefore to the word of the Lord, and returned to depart, according to the word of the Lord."
EGW directly quotes 1 Kings 12:24.