At a local meeting we had a discussion on the four main views of salvation that Christians have adoped. They are:
Here's my take on it - the arguments of the religious pluralists and the inclusivists are usually against a straw version of the Salvation through Christ positions. For instance, they say that it would not be reasonable to say that God simply hasn't spoken through those other religions. I agree fully. But that's not what the Salvation through Christ options say. Take Acts 17, for instance. This is one of my favorite passages of scripture. In this passage, Paul makes it known very clearly that he thinks that God has indeed been working in the religion of the Greeks. He quoted their poets as giving truth, and gave credence to one of their altars as an altar to the true God. Yet this is how he ended his sermon "...but now he commands all people everywhere to repent. For he has set a day when he will judge the world with justice by the man he has appointed. He has given proof of this to all men by raising him from the dead."
Paul is clear - the Greeks did in fact have real (though incomplete) knowledge of God, but they still needed to repent!
When you realize that there is nothing contradictory between God having been active in all religions and God requiring repentance through Christ of all people everywhere, the reasons for taking on the inclusivist or pluralistic options vanish.
So what about those who haven't heard? My take on it is somewhat of a middle road between Salvation through Christ and Salvation through Christ alone.
Look through the Old Testament. The Old Testament is very clear what the rules are, and what the punishments are for not following the rules. But what happens? People continue to violate those rules. The penalty for this is clear. But what does God do? Sometimes God punishes, but sometimes God shows His mercy.
So my point is that the path of salvation is clear - Christ alone. However, God can choose to mercifully save anyone whom He wants. This is not something we can count on - it's based entirely on God's choice (we often forget that God is not a candy machine - God can choose whatever God wants). He might choose for them to be destroyed - that is the rightful fate of all of us! By His mercy we have a path of salvation. It is not outside of God's character that He might offer additional mercy to others. However, unlike the "Salvation through Christ unless you haven't heard" position, God is under no obligation, and there is no system, for the salvation of those who have not heard.
What does God say about people who haven't heard, and its not their fault? See Ezekiel 33:
When I bring the sword against a land, and the people of the land choose one of their men and make him their watchman, and he sees the sword coming against the land and blows the trumpet to warn the people, then if anyone hears the trumpet but does not take warning and the sword comes and takes his life, his blood will be on his own head. Since he heard the sound of the trumpet but did not take warning, his blood will be on his own head. If he had taken warning, he would have saved himself. But if the watchman sees the sword coming and does not blow the trumpet to warn the people and the sword comes and takes the life of one of them, that man will be taken away because of his sin, but I will hold the watchman accountable for his blood.
Even if they are not warned by the watchmen, they are still taken away by judgment. God might be gracious - but we have no guaranties.
Bosch reports on a report which has a very interesting quote:
"We cannot point to any other way of salvation than Jesus Christ; at the same time we cannot set limits to the saving power of God... We appreciate this tension, and do not attempt to resolve it"
I think there are true believers of God in other religions. Look at what God did with Cornelius (see Acts 10). Do you think God has stopped doing that? If so, you should take a look at what's happening in the Muslim world:
"Many people are having dreams. They see Jesus appear to them. Probably half our pastors were leaders, imams in Moslem mosques. They were leaders in these mosques, now they're pastors."
I have a friend that is familiar with some of these happenings. It is a truly wonderful work of God!