Anyone interested in “The Gifts and the Calling of God are Irrevocable” might also be interested in Matthew Levering, Christ's Fulfillment of Torah and Temple: Salvation according to Thomas Aquinas: http://www.amazon.com/Christs-Fulfillment-Torah-Temple-Salvation/dp/0268022739/ref=sr_1_1?ie=UTF8&qid=1449846803&sr=8-1&keywords=levering+torah+temple

Unlike the recent non-magisterial document, Thomas's view is based on a sound interpretation of Scripture and Catholic belief.  The document more or less either ignores or sets aside the important distinctions and issues that Thomas addresses.