We sometimes ask, 'What of the good men and women who lived before the time of Christ or in pagan lands, and never had the opportunity of being Christians?' Here is the answer of one writer.
We must believe that the possibilities, provided by God of learning through suffering in this world, have always afforded a sufficient means of salvation to every soul that has made the best of the spiritual opportunity offered to it here, however small that opportunity may have been...
A pagan soul, no less than a Christian soul, has ultimate salvation within its reach; but a soul which has been offered, and has opened itself to the illumination and grace that Christianity conveys, will, while still in this world, be more brightly infused with the light of the other world than a pagan soul that has won salvation by making the best of this world, of the narrower opportunity here open to it. The Christian soul can attain, while still on earth, a greater measure of human goodness than can be attained by any pagan soul in this earthly stage of its existence...
It is this individual spiritual progress in this world for which we pray when we say, 'Thy will be done on Earth as it is in Heaven'. It is for the salvation that is open to all people of good will—pagan as well as Christian, primitive as well as civilized—who make the most of their spiritual opportunities on earth, however narrow these opportunities may be, that we pray when we say, 'Thy Kingdom come'.
~ Arnold J. Toynbee, Civilization on Trial