1 Kings 1:24

And Nathan said, My lord, O king, hast thou said, Adonijah shall reign after me, and he shall sit upon my throne?

Nathan put to David the pointed question whether he had himself declared that Adonijah would reign after him and sit upon his throne. The question laid directly before the king Adonijah's move to take the kingship for himself. That move was a seizure of power in opposition to God's appointment of Solomon as David's successor.