The Westminster Assembly’s Directory for the Publick Worship of God rightly understands the above petition to be a promise that the Church will ultimately calvinize all the World. That
includes de-brainwashing heretics — and redirecting them toward the untruncated Word of God.
For in its ‘Publick Prayer before the Sermon’ the Minister is "to pray for the propagation of the Gospel and Kingdom of Christ to all nations — for the conversion of the Jews; the fulness of the Gentiles; the fall of Antichrist." He is also to pray: "for the deliverance of the distressed churches abroad from the tyranny of the antichristian faction and from the cruel oppressions and blasphemies of the Turks [alias the Muslims]; for the blessing of God upon the Reformed Churches"; and for God to "establish…the purity of all His ordinances, and…remove heresy."