Charles Spurgeon Commentary Isaiah 48:4-5

"Because I knew that thou art obstinate, and thy neck is an iron sinew, and thy brow brass; therefore I have declared it to thee from of old; before it came to pass I showed it thee; lest thou shouldest say, Mine idol hath done them, and my graven image, and my molten image, hath commanded them." — Isaiah 48:4-5 (ASV)

See the care of God towards the most obstinate of people. He knows that they will pervert things, so he prevents them as far as it is possible to do so. He tells them what is to happen, that they may not afterwards say that their idol gods have done it.

Ah, dear friends, God has taken great interest in many of us! He has, as it were, laid his plans to keep us out of sin; and yet often we have broken out, and have gone over hedge and ditch in the ways of sin. We have seemed resolved to do evil; we have been desperately set on mischief; therefore he speaks of us as being "obstinate."

Thy neck is an iron sinew, and thy brow brass. Will God ever speak in mercy to such people as these? We will see as we read on.