2 Chronicles 36:13 Commentary - English Annotations on the Holy Bible by Matthew Poole
Who had made him swear by God; who had required and forced him to swear fealty and constant obedience to him by the true God, whom he had served, and whom he called upon to be a witness against him if he broke his oath. So his rebellion was aggravated with perjury, and horrid contempt of God. Compare Eze 17:18. Hardened his heart, i.e. he added obstinacy and incorrigibleness to his sins.
Consult other comments:
2 Chronicles 36:13 - Albert Barnes' Notes on the Bible
2 Chronicles 36:13 - Joseph Benson’s Commentary on the Old and New Testaments
2 Chronicles 36:13 - The Cambridge Bible for Schools and Colleges
2 Chronicles 36:13 - Companion Bible Notes, Appendices and Graphics
2 Chronicles 36:13 - Ellicott's Commentary for English Readers (Old and New Testaments)
2 Chronicles 36:13 - John Gill's Exposition of the Entire Bible
2 Chronicles 36:13 - English Annotations on the Holy Bible by Matthew Poole
English Annotations on the Holy Bible by Matthew Poole

Matthew Poole (1624–1679) wrote English Annotations on the Holy Bible, completing the chapters as far as Isaiah 58 before his death in 1679. The rest of the Annotations were completed by friends and colleagues among his Nonconformist brethren. The first printing of the completed edition was in 1685, 2 volumes folio, followed by editions in 1688, 1696 (with valuable chapter outlines added by the editors, Samuel Clark and Edward Veale), and the 4th and definitive edition in 1700, the basis of all others.