A prominent conservative cardinal has issued a stern warning against “ideological lobbies,” including what he referred to as the “gay lobby,” ahead of the upcoming papal election.

German Cardinal Gerhard Ludwig Müller, a vocal critic of the late Pope Francis, called for the Church to reaffirm its traditional teachings and urged the next pontiff to be “strong on doctrine” and unwavering in the face of increasing liberal pressures.

In an interview with Italy’s La Stampa, Cardinal Müller stressed that the new Pope must possess “solid theological and doctrinal formation” and remain steadfast against what he described as the growing threats of “heresy” and “gender ideology.”

“Doctrine is not the property of the Pope, the bishops, or the faithful,” Müller asserted. “It must conform to the word of Jesus. No one can modify it. If Jesus says marriage is between a man and a woman, no one can change that doctrine.”

The outspoken cardinal also condemned any attempts to equate marriage with same-sex unions, calling it a direct contradiction to biblical teachings.

Müller’s remarks come as cardinals from around the world meet in Rome to finalize the schedule for the upcoming conclave, set to begin on May 7. This follows the death of Pope Francis, who passed away last week at the age of 88 after suffering a stroke and heart failure.