What does Isaiah 7:10 mean?

It is not known whether this continues the conversation between Isaiah and Ahaz in the previous verses (Isaiah 7:4–9) or whether it takes place later. Isaiah, though, clearly understands the Lord is speaking to Ahaz through him. This message is fully God's. Isaiah was not a typical counselor to the king, in the sense of offering ideas for the king to take or leave. He was the Lord's voice in the king's ear—the king could receive or reject that revelation from God.

The same is true now, for everyone who reads the Bible. It is not merely writings of ancient people with interesting ideas. The words are not one set of options among many. They are the words of the Lord delivered through the pen of those writers as revelation from God Himself. We must also choose whether to receive or reject it, and we should study it.