Notice the wording here. He is talking about fear.
The historical background here was that Judah felt threatened by the presence of the Assyrian empire. They were sweeping down on all of the nations and conquering them. Judah was frightened by them. Now as the people of God, what should they have done? In deep respect, awe, and faith they should have cried out to God and asked for His protection. He is the Lord of heaven and earth. He governs it all. He could have stopped the Assyrians. But instead of doing that, the people conspired with other nations and said to them, in effect, You be our protection. We will make alliances with you. We are afraid of the Assyrians, but if we join together in an alliance, we will have enough power to fend them off and we will be safe.
God looked upon that as a conspiracy against Him. He was their Lord. He was their God. He was their King. And He had the power to protect. And thus, the instruction to Isaiah, Do not enter into that conspiracy with them.
Just in case we thought it was sufficient to stand only in reverence or awe or respect of Him, Isaiah added, Let Him be your dread! And He is asking, in effect, Of whom are you more afraid, the Assyrians or Me? Verse 14 is most interesting: If we make Him our fear and our dread. . .
There is a very interesting comment in the Interpreter's Bible Commentary regarding this series of verses. They saw very clearly that what God was instructing Isaiah to do was to turn away from the bulk of the Israelites and turn his message to a tiny remnant of a people who were willing to be obedient and faithful in response to their God. He is telling him to turn away from the main body and pay attention to that small group, the remnant that wants to be faithful to God. And He said, I will become a snare to those who are turning away from Me and I will be a trap. They will stumble as a result of not having the fear of God and because they are faithless.
It is interesting that God does not seem the least bit worried that His people should have a dread of Him. Indeed, this dread, rather than being a hindrance to a proper relationship with Him, is clearly seen as producing a positive benefit. He becomes a sanctuary, a place of abode, and a place to which we can run for safety. He is a place of safety for those who are afraid of Him!
When this process begins none of us may be able to give reasons as to why we are doing what we are doing until much later on. But that strong hand (about which we just read in Isaiah 8 and that constrained Isaiah to react in the way that he did and not go along with the people who were talking conspiracy against God, but to turn to those who were faithful to God) compels us to begin to react to God in the way that we do and has brought us to the point we are at right now.
