That is not the sense in which Fr. Cantalamessa means "conversion." The word has deeply spiritual meanings. Conversion is the duty of every Christian -- to "turn towards" to "repent" to become more like Christ. It is the heart of Christianity.
Anyway, reflecting on the readings for the Third Sunday of Lent, this is what Fr. Cantalamessa has to say (after an interesting aside that takes a swipe at some of the problematic presuppositions of some modern biblical schoalrship, especially in the Bultmannian mode):
Let us go back, as we usually do, to this Sunday's Gospel passage to glean some practical guidance. Jesus comments on Pilate's butchery and the collapse of the tower thus: "Do you think that these Galileans were worse sinners than all the other Galileans because they suffered in this way? No, I tell you; but unless you repent you will all likewise perish." We deduce a very important lesson from this. Such disasters are not, as some think, divine castigation of the victims; if anything, they are an admonition for others.(As is his wont, or better, his duty as the preacher to the Papal Household, he will give various reflections over the course of Lent. Zenit has the summary of this year's first, on hypocrisy. Even [especially?] among the religious. Read it.)
This is an indispensable interpretive key which allows us to see that we should not lose faith when we are confronted with the terrible events that occur every day, often among the poorest and most defenseless. Jesus helps us to understand how we should react when the evening news reports earthquakes, floods, and slaughters like that ordered by Pilate. Sterile reactions like, "Oh those poor people!" are not what is called for.
Faced with these things we should reflect on the precariousness of life, on the necessity of being vigilant and of not being overly attached to that which we might easily lose one day or the next.
The word with which Jesus begins his preaching resounds in this Gospel passage: conversion. I would like to point out, however, that conversion is not only a duty, it is also a possibility for all, almost a right. It is good and not bad news! No one is excluded from the possibility of changing. No one can be regarded as hopeless. In life there are moral situations that seem to have no way out. Divorced people who are remarried; unmarried couples with children; heavy criminal sentences ... every sort of bad situation.
Even for these people there is the possibility of change. When Jesus said that it was easier for a camel to pass through the eye of a needle than for a rich person to enter the kingdom of heaven, the apostles asked: "But who can be saved?" Jesus' answer applies even to the cases I have mentioned: "For men it is impossible, but not for God." (Emphases added).