Bishop Peter Kohlgraf of Mainz has opposed the recently published "Frankfurt Declaration" of reform-oriented Catholics.
He will not sign this declaration with a number of self-commitments, Kohlgraf said on Wednesday in Mainz.
The clergyman criticized that the result of the consultations on the synodal path was anticipated.
"If I now make commitments before the consultations are completed, I don't think there is a need for further debate."
The signatories to the "Frankfurt Declaration" pledge to support gender equality in the church and to implement it consistently.
It goes on to say: "We oppose any discrimination in the church and give space to all people in their diversity and uniqueness."
The statement has already been joined by the chairman of the German Bishops' Conference, Bishop Georg Bätzing of Limburg, and the President of the Central Committee of German Catholics (ZdK), Irme Stetter-Karp.
In a written statement, Kohlgraf assured that he "would be happy to continue to participate with great commitment in the synodal path".
Kohlgraf was also critical of the initiative of eleven vicars general of the Catholic Church, who called for a waiver of labor law sanctions for church employees because of their private lifestyle.
These related to the #OutInChurch initiative, in which 125 church employees committed themselves to a queer way of life, i.e. to a private lifestyle beyond traditional concepts of male and female identities.
Kohlgraf wrote in response to the vicar general's letter that he could not agree with the attitude "that every aspect of private life was irrelevant to official service".