Amen, I say to you, until heaven and earth pass away, not the smallest letter or the smallest part of a letter will pass from the law, until all things have taken place.
Iota Unum, written by the late Romano Amerio who passed away in 1997, is a magisterial study of change in the Catholic Church in the last century. Amerio took his title from Christ’s statement in Matthew 5:18 that begins this post. Amerio began the work in 1935 and published it in 1985. Born on June 22, 1905 in Lugano, Switzerland, Amerio was a Roman Catholic theologian as well as a philologist and philosopher. He served as a peritus (theological expert) at Vatican II and was an advisor to Cardinal Guiseppe Siri.
Intensely critical of most of the changes implemented after Vactican II, Amerio essentially became a non-person in Vatican circles after the publication of Iota Unum. A review prepared for L’osservatore Romano, for example, in 1985 was not published. The pontificate of Pope Benedict ushered in a change of view as to Iota Unum. A good overview of Iota Unum and its reception, written by Father Richard Whinder, is here. Sandro Magister has a fine article here on Iota Unum. Here is an earlier article from 2007 by Sandro Magister when the silence about Iota Unum at the Vatican was broken. (Hattip to Father Z. I was unaware of the book Iota Unum until I read this post by him.)