41 Furthermore, there is another reason which demands the immediate coalition of all ranks under the single sign of the cross in order to oppose the turbulent attacks of the infernal enemy. Who is not horror struck at the ferocity and hatred with which the enemies of God, in many parts of the world, threaten to eradicate and wipe out everything divine and Christian? All those who are signed with the sacred character of baptism and are deputed by their state to fight the good fight of Christ, cannot remain disunited and dispersed against the confederated ranks of their enemies.
Source: Sempiternus Rex Christus (Vatican.va)