Why am I not surprised that Benedict XVI has edged away from the Vatican's previous opposition to the use of condoms in HIV prevention? The answer might be that this pope is, above all else, a theologian.

While his grassroots pastoral experience is as limited as his academic record is huge, he is strongly aware of the centrality of "development" as a key principle of all Catholic teaching. This enables the Catholic hierarchy to forbid something one day and make it compulsory weeks later; for a pope to assert in doctrinal statements, "as my venerable predecessors have always taught", when patently they have not.

So what is Benedict's track record? Shortly after his election as pope in 2005, he addressed a Rome Diocesan conference on the family. Even if the application of his remarks seemed inconsistent, he delicately overturned John Paul II's "theology of the body", indicating principles of "humanisation" rather than "idealisation" in the realm of sexuality. He returned to this in comments on his flight to Africa in March 2009, when he spoke about "the humanisation of sexuality". The media then picked upon his apparent rejection of condom use in HIV prevention, rather than understanding the more affirming theological context on which Benedict was reflecting. While journalists constantly attributed explicit condemnation of condom use to John Paul II, he never used the word, and it was the present pope who first spoke explicitly about their role in HIV prevention, even using the colloquial Italian word for "condom", speaking about condoms as a means of HIV prevention, not as a birth-control method.

Those who have dealt with the pope, both as prefect of the Congregation for the Doctrine of the Faith and as bishop of Rome, affirm his readiness to listen and engage in argument, rather than pontificate vociferously, unlike his predecessor. Some Catholic theologians suggest that Cardinal Ratzinger moderated the language of CDF documents on homosexuality, written not by him but by other Vatican officials, as well as clarifying previously harder-line criticisms of liberation theology. In 1999, Ratzinger affirmed, during an informal in-flight conversation with Sister Jeannine Gramick who was under CDF investigation, that her conscientious dissent on pastoral ministry with lesbian and gay Catholics did not fall within the scope of the church's excommunicable offences.

Despite fundamentalist Catholics in the UK, opposed to better-informed pastoral ministry with lesbian, gay, bisexual and transgendered Catholics, baying for condemnations, no such criticisms were made during the recent papal visit, nor indeed were matters of sexual ethics or same-sex unions even mentioned.

Do Benedict's comments indicate a radical change in Catholic HIV prevention policies? I think not. What is obvious is that Catholics and agencies working in development, HIV prevention and support, will heave a sigh of relief that they do not have to keep looking over their shoulder as conservative Catholics try to undermine their comprehensive HIV strategies. The evidence-based and comprehensive approaches by agencies like Caritas Internationalis now have a papal endorsement.

Unforeseen implications may have been drawn from the papal interview insofar as the German word for prostitute is a masculine noun whereas in Italian it is feminine, so the pope might well have intended broader gender inclusion that would embrace serodiscordant couples, where one person is HIV positive and the other not, whether within marriage or not. What is not in doubt in any of these comments, including those on the need to ponder sexual ethics issues more deeply, is that the pope seems to be endorsing the principle of Catholic moral theology known as "gradualism".

Heavily criticised by John Paul II (in his 1993 encyclical letter, Veritatis Splendor) this approach recognises that moral decision making is a step-by-step process. Progressive Catholic theologians, including bishops and cardinals, have applied this principle to a range of sexual ethics questions, including HIV issues, civil law and abortion, and sexual orientation law reform. Who knows, perhaps this might open the door even to a direct papal dialogue with the victims of abuse, people living with HIV, and God's lesbian, gay, bisexual and transgendered daughters and sons?

Returning from El Salvador on the day the papal remarks were leaked, I was reminded of the Contrasida Project, directed by a remarkable American nun who is also a physician. Although supported by Catholic development agencies around the world, Contrasida was forced to cut its links with the San Salvador Archdiocese, during the tenure of its previous conservative archbishop, because it adopted a comprehensive prevention programme, choosing to work alongside secular HIV groups and those working with the gay and trangendered communities. Such projects have more than enough burdens to carry with the lack of financial resources, readily available and effective medications, and suitable premises, without the church's pastors heaping on more.

Addressing the newly created cardinals this past weekend, the pope reminded them of the role of St Peter to strengthen his sisters and brothers in faith. In his comments on HIV prevention and sexual ethics, he appears to have responded to another biblical injunction: to lift burdens from those who might be heavy-laden.