From Church Society: “A Faith for Today: A Commentary on the Thirty-Nine Articles” by Bp. Donald Allister
If you would like a relatively brief commentary and overview of the Thirty-Nine Articles of Religion – and one in modern language at that – Church Society has A Faith for Today: A Commentary on the Thirty-Nine Articles available in PDF on their site. This text is by Donald McAllister, who is now Bishop of Peterborough. In only 39 pages he does an excellent overview of the background of the Articles and their doctrine.
Combine this short book with The Anglican Faith: A Layman’s Guide by the Rev. Dick Begbie and you will have two very good books on the Articles that have been produced in the last forty years.