Near the beginning of the video of the visit (below) an old Jewish man greeted the Pope and then says to him: "Senta, siccome Lei un grande ricostruttore, perché non mette "la circoncisione" un altra volta nel calendario come... quando ero ragazzino, è una buon'idea, non? Sarebbe per noi..."
"Look, since you're a great rebuilder, why not put The Circumcision once again into the calendar as it was when I was a little boy? It's a good idea, don't you think? It would be for us..."
The re-naming of the feast of 1st Jan is one of the odd and unsatisfactory things about the 1962 Calendar. Unsatisfactory, because the solution they came up with in 1962 - renaming the 'Circumcision', 'the Octave of Christmas', didn't satisfy the reformers only a few years later, when it was renamed 'the Feast of the Holy Mother of God'. It is the only one of the ten Days of Obligation listed in Canon law where the name is different in the 1962 Calendar and the 1970 one.
The theme of the circumcision came into the Roman calendar from Gallican sources, something which made it unpopular with the minimalist fanatics of the era of reform. But it is of great significance: that Jesus was a Jew, and submitted to the Law of Moses in this concrete way, even as a tiny baby.