The three lights

Martin Luther:

Let us take it that there are three lights – the light of nature, the light of grace, and the light of glory, to use the common and valid distinction. By the light of nature it is an insoluble problem how it can be just that a good man should suffer and a bad man prosper; but this problem is solved by the light of grace. By the light of grace it is an insoluble problem how God can damn one who is unable by any power of his own to do anything but sin and be guilty. Here both the light of nature and the light of grace tell us that it is not the fault of the unhappy man, but of an unjust God; for they cannot judge otherwise of a God who crowns one ungodly man free from merits, yet damns another who may well be less, or at least not more, ungodly. But the light of glory tells us differently, and it will show us hereafter that the God whose judgment here is one of incomprehensible righteousness is a God of most perfect and manifest righteousness. In the meantime, we can only believe this, being admonished and confirmed by the example of the light of grace, which performs a similar miracle in relation to the light of nature.

(pp. 332, The Bondage of the Will, in Ernest Gordon Rupp, Desiderius Erasmus, Philip Saville Watson e.d., Luther and Erasmus: Free Will and Salvation)

Gavin Ortlund:

Luther also distinguishes between the light of nature, the light of grace, and the light of glory. I find this distinction very helpful. Just as there are many things that we see in the light of grace that we could not possibly understand by the light of nature, so there will be much that we will see in the light of glory that we cannot possibly understand in the light of grace. Therefore Christian faith has a drama, a mystery, and a tension to it as it waits for the eschatological vindication of its content.