 In Isaiah we see the coalescing of influences from both the histories of the northern kingdom of Ephraim and the southern kingdom of Judah. The heritage of the northern kingdom plays a high priority on obedience to God and keeping God's law, while the southern kingdom took great pride and God's promise to always be on their side. The prophet Isaiah holds these two worldviews together, encouraging the king to remember God's promise and be confident in it, and yet not to be lax in following God's law.