Luther's Complete Sermon for Judica
If one could only believe it and persevere, he will surely come. “Verily, verily, I say unto you, if a man keep my word, he shall never see death.”
8. By these words he spoils it entirely, in that he does not only defend his doctrine as right and good, which they attribute to the devil; but also ascribes such virtue to his teaching that it becomes a powerful emperor over Satan, death and sin, to give and sustain eternal life. Behold here, how divine wisdom and human reason conflict with one another. How can a human being grasp the thought, that a corporeal, an oral word should redeem forever from death? But let blindness run its course; we shall consider this beautiful saying. Christ is speaking here not of the word of the law, but of the Gospel, which is a discourse about Christ, who died for our sins etc. For God did not wish to impart Christ to the world in any other way; he had to embody him in the Word and thus distribute him, and present him to everybody; otherwise Christ would have existed for himself alone and remained unknown to us; he would have thus died for himself.
But since the Word places before us Christ, it thus places us before him who has triumphed over death, sin and Satan. Therefore he who grasps and retains Christ, has thus also eternal deliverance from death. Consequently it is a Word of life, and it is true, that whoever keeps the Word shall never see death.