A few times in the past, I have noted that there are some interesting aspects to the differences between the lectionaries in the ancient and new roman rites. Dr. Taylor Marshall did some intersting work on the matter and so did Una Voce.
Thanks be to God Matthew Hazell has also released a new book on the matter called "Index Lectionem" which Joseph Shaw of LMS did a short write up on recently. A few excerpts from the Shaw piece below:
"No doubt for different reasons, the following two verses, 1 Corinthians 10:7-9, part of the Traditional Lectionary for the 9th Sunday After Pentecost, are totally excluded from the 1970 Lectionary.
Neither become ye idolaters, as some of them, as it is written: The people sat down to eat and drink, and rose up to play. Neither let us commit fornication, as some of them committed fornication, and there fell in one day three and twenty thousand. Neither let us tempt Christ: as some of them tempted, and perished by the serpents.
So is this passage, of a quite different character, across Romans 12:17–21, used in the old Lectionary as part of the Epistle of the 3rd Sunday After the Epiphany:
To no man rendering evil for evil. Providing good things, not only in the sight of God, but also in the sight of all men. If it be possible, as much as is in you, have peace with all men. Revenge not yourselves, my dearly beloved; but give place unto wrath, for it is written: Revenge is mine, I will repay, saith the Lord. But if thy enemy be hungry, give him to eat; if he thirst, give him to drink. For, doing this, thou shalt heap coals of fire upon his head. Be not overcome by evil, but overcome evil by good.
Dr Kwasniewski gives more examples, and the book sets out the whole thing in detail. None of this would be surprising if the reform of the Lectionary did not have as its chief publicly stated purpose (and the only purpose given it by the Second Vatican Council), that of providing a larger selection of scriptural texts. It is indeed a larger set of texts, but they still went to amazing trouble to exclude texts they didn't like, for a variety of reasons, from use. Some are buried among scores of options given for votive Masses unlikely ever to be considered, let alone used; others are completely absent."
You can read the full write-up HERE
You can purchase the text HERE