BRUSSELS — A Belgian bishop has lashed out at the Vatican over its decree that the Catholic Church won’t bless same-sex unions since God “cannot bless sin.”

Antwerp Bishop Johan Bonny wrote in an opinion piece Wednesday that he feels “shame for my Church” and “intellectual and moral incomprehension” after Pope Francis approved the “negative” response to a question about whether Catholic clergy have the authority to bless same-sex unions. The official response said God “does not and cannot bless sin.”

Bonny, who was part of a Vatican 2015 synod on marriage and family, said: “I want to apologize to all for whom this is painful and incomprehensible.”

The conference of Belgian bishops backed Bonny’s concerns, saying LGBT faithful and their families saw the Vatican decree as “exceptionally painful.” The conference urged everyone to work on “a climate of respect, recognition and integration.”

The Vatican’s position has pleased conservatives, disheartened advocates for LGBT Catholics and thrown a wrench into a debate within Germany’s Catholic Church, which has been at the forefront of opening discussions on hot-button issues such as Catholic teachings on homosexuality.

Bonny said he was disappointed by the level of argument that ran through the note from the Vatican’s orthodoxy office, the Congregation for the Doctrine of the Faith.

“Intellectually, this does not even reach the level of high school. These kind of arguments, the logic, you see right through it. These days, you don’t convince anyone that way,” Bonny said.

The Congregation’s note distinguished between blessing same-sex unions and the church’s welcoming and blessing of gay people, which it endorsed. It argued that such unions were not part of God’s plan and that any sacramental recognition of them could be confused with marriage.

The Vatican holds that gay people must be treated with dignity and respect, but that gay sex is “intrinsically disordered.” Catholic teaching says that marriage is a lifelong union between a man and a woman that is part of God’s plan and intended for creating new life.

The orthodoxy office’s document argued that same-sex unions can’t be blessed by the Catholic Church because they are not part of that plan.

God “does not and cannot bless sin: He blesses sinful man, so that he may recognize that he is part of his plan of love and allow himself to be changed by him,” the note said.

In his opinion piece published in Belgian newspaper De Standaard, Bonny countered that “sin is one of the most difficult theological and moral categories to define, and one of the last to pin on people and their way of living together.”

The Congregation for the Doctrine of the Faith issued a similar decree in 2003 that said the church’s respect for gay people “cannot lead in any way to approval of homosexual behavior or to legal recognition of homosexual unions.”

Belgium has historically been a staunch Catholic country with strong ties to the Vatican. But the number of believers and attendance at church services has shrunk over the past decades.

The nation is dotted with churches great and small, but their death announcements almost invariably outnumber those for baptisms.