Well we probably could agree that Lincoln was right, but we might not agree on what makes him right.
If your values are not founded on some form of transcendent ethic or value, what makes Lincoln right? Majority opinion? Personal conviction?
......... Lincoln was of course highly religious but not Christian orthodox.
I should say you have very good philosophical questions.
Here's my take. For me, it does not matter 'what makes Lincoln 'right''.
'Lincoln is right', is all that matters.
Now, why is that so. Because, what makes Lincoln believe in what he believs in is not my concern. In the temporal sense. For example; whether his religion, his influences, his experiences that is basically his background is not the basis on which one thinking man deals with another thinking mans idea, proposition, theory or observation.
The factor of majority opinion may, very much play a role in an unthinking man, if you get what i mean. Can't disregard that.
Personal conviction, is always in a state of flux. A thinking man may not rely on this for support. Social reform movements have always changed personal convictions.
Without some conception of god, ethics and morality encounters a void which has yet to be satisfactorily filled. I personally reject both the death of values and the death of god but that was the point of the question. If that value is not founded in god, in what?
When you say values, i think you are refering to moral values, isn't it?
You raise some deep issues. I am frankly not clear, how to answer not only because that i have not fully understood or grasped your point, but even going by whatever i may have understood, more or less, I am unable to gather my thoughts to address the issue.
So, cautiosly, i think your question is rooted in the concept of morals, and foundation of morals in human thoughts.
God, is a representation of Reality..... the unknown reality.... the impercitable one......... Moral values are attributed to God because for humans it appears to be the source of all moral laws, compassion, love and other worthy emotions that hold society to gather. While the unworthy emotions, which is said to cause the breaking of society is attrivuted to the devil, in the christian/islamic view-point.
God is nothing but the moral sense of the Society. The Individual makes sense of Society through the means of God. And vice versa. This is a social theory. It was proposed a century ago by a social scientist whose name i can't remember. I hope this may help. Thanks