We cannot truly call on God, the Father of all, if we refuse to treat in a brotherly way any man, created as he is in the image of God. Man’s relation to God the Father and his relation to men his brothers are so linked together that Scripture says: “He who does not love does not know God” (1 John 4:8).
No foundation therefore remains for any theory or practice that leads to discrimination between man and man or people and people, so far as their human dignity and the rights flowing from it are concerned.
The Church reproves, as foreign to the mind of Christ, any discrimination against men or harassment of them because of their race, color, condition of life, or religion. On the contrary, following in the footsteps of the holy Apostles Peter and Paul, this sacred synod ardently implores the Christian faithful to “maintain good fellowship among the nations” (1 Peter 2:12), and, if possible, to live for their part in peace with all men, so that they may truly be sons of the Father who is in heaven. – from Nostra Aetate (1965)