“The truth contained in these words is of vast importance. They supply an antidote to many crude and unsound notions which are abroad in the world. Christ did not come to be only a teacher of new morality, or an example of holiness and self-denial, or a founder of new ceremonies, as some have vainly asserted. He left heaven, and dwelt for thirty-three years on earth for far higher ends than these. He came to procure eternal life for man, by the price of His own vicarious death. He came to be a mighty fountain of spiritual life for all mankind, to which sinners coming by faith might drink; and, drinking, might live for evermore. By Moses came laws, rules, ordinances, ceremonies. By Christ came grace, truth, and eternal life.
“Important as this doctrine is, it requires to be fenced with one word of caution. We must not overstrain the meaning of our Lord Jesus Christ’s words. We must not suppose that eternal life was a thing entirely unknown until Christ came, or that the Old Testament saints were in utter darkness about the world to come. The way of life by faith in a Savior was a way well known to Abraham and Moses and David. A Redeemer and a Sacrifice was the hope of all God’s children from Abel down to John the Baptist; but their vision of these things was necessarily imperfect. They saw them afar off, and not distinctly. They saw them in outline only, and not completely. It was the coming of Christ which made all things plain, and caused the shadows to pass away. Life and immortality were brought into full light by the Gospel. In short, to use our Lord’s own words, even those who had life had it “more abundantly,” when Christ came into the world.”
(excerpt from J.C. Ryle’s Expository Thoughts on John, 1869; commentary on John 10:10b)