The church is to live as the alternative polis, not by separating itself into sectarian isolation but by bearing witness, like Daniel and his friends, before kings and rulers. The aim is not to damn, but to redeem; the leaves on the tree are for the healing of the nations, and the gates stand open for the kings of the earth to bring their treasures. Only if we keep that goal before us will we avoid the isolation which is the mirror image of collusion.
— NT Wright