Pope Francis' witnessing of marriages between Catholics who cohabited or who have had annulments is not a change, but is part of the Church's effort to bring people to Jesus Christ, said two experts on Christian marriage.

"I think there is a perception out there, especially in some media circles, that Pope Francis is trying to undermine what the Church has taught and what the Church has practiced," Catholic University of America moral theology professor John Grabowski told CNA Sept. 15.

"I see absolutely no evidence of that. When he's pressed on issues concerning the Church's teaching on marriage, on sexuality, he is very firm, saying he is 'a son of the Church'," Grabowski continued. "What he wants to do is simply put the Church's focus on mercy, on an encounter with Christ as the heart of its life."

On Sept. 14, Pope Francis celebrated the marriages of 20 couples from the Diocese of Rome. In his homily, he told them that Jesus Christ "will bring them healing by the merciful love which pours forth from the Cross, with the strength of his grace that renews and sets married couples and families once again on the right path."

Some media reports have focused on whether some of the couples had annulments or had lived together before marrying. Time magazine claimed that the marriages "hint at coming changes" on divorce and remarriage. The New York Times claimed that the weddings mean that Pope Francis "looks past tradition."

However, Grabowski said he saw no concrete evidence that the Pope is "instituting any kind of sweeping changes."

In fact, the Pope's actions in marrying cohabiting couples reflect common Catholic practice.

"It's not just Pope Francis, it's the whole Church who wants to encourage people who are living in a way that contradicts their baptismal dignity to stop living that way," the professor said.

Catholic teaching holds that cohabitation is "objectively, morally wrong" and on a practical level undermines the prospects of success for marriage. Studies indicate that couples who cohabit before marriage show more propensity to divorce than couples who do not.

Grabowski noted the U.S. bishops' 1999 document on marriage preparation and cohabiting couples.

That document noted the destructive impact of cohabitation and the steps couples can take to change their situation before marriage. These steps included ceasing a sexual relationship until the wedding and going to confession "to try to begin their marriage on a new footing so that this harmful practice doesn't end up undermining their chance at a happy, successful marriage," Prof. Grabowski said.

Msgr. Joaquín Llobell, author of the book "Marriage Procedures in the Church," stressed that marriage and the family "are the first means of God to make us happy here on Earth and to take us to Heaven."

He explained that the Catholic faith sees a distinction between a divorce and a recognition of an invalid marriage, commonly known as an annulment.

Civil divorce "breaks a valid marriage." By contrast, to annul a marriage doesn't "break that which existed." Rather, it is a declaration from the Church that a marriage "was never valid" to begin with.

A man with a previously annulled marriage "will be getting married for the first time" because that previous union was not valid due to a defect in him or in the woman with whom he attempted to enter a martial union. These defects can include matters of intention, like the rejection of having children as a purpose of marriage, or conditions such as mental illness that prevent a true marriage from being joined.

Msgr. Llobell is a canon law professor who has taught at the Pontifical University of the Holy Cross and has served on the tribunal for the Apostolic Signatura.

"What Pope Francis has said most often since becoming Pope is that God is merciful, that we humans exist because God has created us as a manifestation of God's mercy. Therefore the Church, which is the instrument that God gives us to save us, cannot not be merciful. It is always profoundly merciful," the monsignor told CNA ahead of the Sunday weddings.

He said the Church is also merciful in cases of alleged marriage nullity, though these cases are "complicated."

If the Church thinks a marriage is valid, it "cannot but say the truth to its child: 'Your marriage isn't invalid and therefore you can't get married a second time'."

"And that is said with love, explaining why, and with a mercy that is compatible with the truth."

The marriage of cohabiting couples should also not be misinterpreted, Grabowski advised.

He said that a Church marriage for a cohabiting couple is "not a validation of cohabitation" but "a removal of cohabitation."

"It's enabling them to move out of a state that objectively contradicts their Christian profession and their Christian baptism," he said.

The professor noted that canon law "speaks of the freedom of the baptized to marry" and that the Church and its ministers cannot "put any obstacles in the face of that." He said individual priests who have barred cohabiting couples from marrying in their parish have been corrected by their bishops.

This does not mean that Catholics want to encourage couples to cohabit, he explained.

"We don't want to impinge or impede the freedom of the baptized to marry and to move out of what is an objective state of sin," he added.