Are there boundaries which we may not cross? Apparently not, according to the Gospel and the bishops:
49. Jesus’ last words in St. Mark’s Gospel confer on the evangelization which the Lord entrusts to His apostles a limitless universality: “Go out to the whole world; proclaim the Good News to all creation.”[Mk 16:15]
The Twelve and the first generation of Christians understood well the lesson of this text and other similar ones; they made them into a program of action. Even persecution, by scattering the apostles, helped to spread the Word and to establish the Church in ever more distant regions. The admission of Paul to the rank of the apostles and his charism as the preacher to the pagans (the non Jews) of Jesus’ Coming underlined this universality still more.
As the “new” evangelization invites us, perhaps, to something of a penitential outreach to inactive or indifferent believers, it is good to keep in mind that the Lord urged the Church forward. This would not negate the need for believers to seek out and inquire about those missing from the Sunday assembly. But let’s not lose track that we were once called to higher things, in even more dangerous times.