This was originally posted on the Coming Home Network board, where I was head moderator from 2007-2010. My esteemed friend and fellow moderator, David W. Emery wrote:
You will see me speaking of becoming Catholic, for instance, or better, entering into full communion with the Catholic Church. To avoid confusion, I try to reserve the word conversion for its primary meaning: conversion of heart, as in And he shall convert many of the children of Israel to the Lord their God (Luke 1:16 DRV) and He must know that he who causeth a sinner to be converted from the error of his way shall save his soul from death and shall cover a multitude of sins (James 5:20 DRV).
The word is used in its primary sense throughout the Catechism as well. I was unable to locate any passage in which convert or conversion is used to refer to moving from another Christian faith community to the Catholic Church. The official term is “entering into full communion.”
Interesting observations about the word “convert” . . . . The term is certainly widely used and understood in the sense of “conversion” from Protestantism to Catholicism: including in virtually all of the books in recent times that chronicle the journeys of those who eventually are received into the Church or are returning to it. G. K. Chesterton wrote a book entitled The Catholic Church and Conversion”
The Catechism of the Catholic Church often uses the term “conversion” in referring to “renewal” of those who are already Christians or even Catholic Christians (somewhat analogously to the popular usage of going from Protestant to Catholic, which is certainly a renewal or adoption of the fullness of the faith and spirituality):
1423 It is called the sacrament of conversion because it makes sacramentally present Jesus’ call to conversion, the first step in returning to the Father from whom one has strayed by sin. It is called the sacrament of Penance, since it consecrates the Christian sinner’s personal and ecclesial steps of conversion, penance, and satisfaction.
1428 Christ’s call to conversion continues to resound in the lives of Christians. This second conversion is an uninterrupted task for the whole Church who, “clasping sinners to her bosom, [is] at once holy and always in need of purification, [and] follows constantly the path of penance and renewal.” This endeavor of conversion is not just a human work. It is the movement of a “contrite heart,” drawn and moved by grace to respond to the merciful love of God who loved us first.
1429 St. Peter’s conversion after he had denied his master three times bears witness to this. Jesus’ look of infinite mercy drew tears of repentance from Peter and, after the Lord’s resurrection, a threefold affirmation of love for him. The second conversion also has a communitarian dimension, as is clear in the Lord’s call to a whole Church: “Repent!” St. Ambrose says of the two conversions that, in the Church, “there are water and tears: the water of Baptism and the tears of repentance.”
1435 Conversion is accomplished in daily life by gestures of reconciliation, concern for the poor, the exercise and defense of justice and right, by the admission of faults to one’s brethren, fraternal correction, revision of life, examination of conscience, spiritual direction, acceptance of suffering, endurance of persecution for the sake of righteousness. Taking up one’s cross each day and following Jesus is the surest way of penance.
The search function for the Catechism lists 68 instances of “conversion”.
The secular meaning is simply to change from one thing to another: converting to, for example, the metric system; converting miles to kilometers, etc.
It’s true that the Catechism doesn’t seem to use the term in the sense of “one who goes from Protestant to Catholic.” In writing about Blessed John Henry Cardinal Newman in 1979, however, Pope St. John Paul II, used the term in that way:
By insisting that the Church must be prepared for converts, as well as converts prepared for the Church , he already in a certain measure anticipated in his broad theological vision one of the main aims and orientations of the Second Vatican Council and the Church in the post-conciliar period.
Vatican II used the word in the “popular” sense in Sacrosanctum Concilium (Constitution on the Sacred Liturgy):
And a new rite is to be drawn up for converts who have already been validly baptized; it should indicate that they are now admitted to communion with the Church.
Zenit Magazine, in a piece printed on the Vatican website, does the same:
Here are excerpts from the text of U.S. Senator Sam Brownback’s commencement address at Ave Maria Law School delivered on May 18. The Republican from Kansas is a recent convert to Catholicism.
Pope Benedict XVI, writing about Cardinal Newman in 1990, stated:
Newman had become a convert as a man of conscience; it was his conscience that led him out of the old ties and securities into the world of Catholicism, which was difficult and strange for him. But this way of conscience is everything except a way of self-sufficient subjectivity: it is a way of obedience to objective truth.
Kevin Flannery, of the Pontifical Gregorian University, states in another item posted at the Vatican website:
The most important “privileged way” by means of which the Church promotes Christian culture is certainly the Eucharist. This is the means by which she has drawn people to herself from the beginning. One need only recall the many Catholic convert authors who say that they were attracted to the Church by the Mass.
Therefore, this usage is by no means impermissible. As with most terms, context is often key to properly understanding the meaning.
Photo credit: G. K. Chesterton, photographed by Ernest Herbert Mills, 1909 [public domain / Wikimedia Commons]