Because I knew that {e} thou art obstinate, and thy neck is an iron sinew, and thy brow brass;

(e) I have done for you more than I promised, that your stubbornness and impudency might have been overcome.

Wesley's Notes

48:4 I knew - Therefore I gave thee clearer demonstrations of my nature and providence, because I knew thou wast an unbelieving nation. Thy neck - Will not bow down to receive my yoke. Thy brow - Thou wast impudent.

King James Translators' Notes

obstinate: Heb. hard

Jamieson-Fausset-Brown Bible Commentary

4. obstinate-Hebrew, "hard" (De 9:27; Eze 3:7, Margin).

iron sinew-inflexible (Ac 7:51).

brow brass-shameless as a harlot (see Jer 6:28; 3:3; Eze 3:7, Margin).

Matthew Henry's Concise Commentary

48:1-8 The Jews valued themselves on descent from Jacob, and used the name of Jehovah as their God. They prided themselves respecting Jerusalem and the temple, yet there was no holiness in their lives. If we are not sincere in religion, we do but take the name of the Lord in vain. By prophecy they were shown how God would deal with them, long before it came to pass. God has said and done enough to prevent men's boasting of themselves, which makes the sin and ruin of the proud worse; sooner or later every mouth shall be stopped, and all become silent before Him. We are all born children of disobedience. Where original sin is, actual sin will follow. Does not the conscience of every man witness to the truth of Scripture? May the Lord prove us, and render us doers of the word.