Have you ever asked why God's forgiveness is of any value? Or what about eternal life? Have you ever asked why you want eternal life? These questions matter because it is possible to want forgiveness and eternal life for reasons that may well indicate that you don't have them.
Take forgiveness, for example. You might want God's forgiveness because you are so miserable with guilt feelings. You just want relief. If you can believe that He forgives you, you will have some relief, but not necessarily salvation. If you want forgiveness only because of emotional relief, you won't have God's forgiveness. He does not give it to those who use it only to get His gifts and not Himself.
Or you might want to be healed from a disease or get a good job or find a spouse. Then you hear that God can help you get these things but that first your sins have to be forgiven. Someone tells you to believe Christ died for your sins, and that if you believe this, your sins will be forgiven. So you believe only in order to remove the obstacle to health and job and spouse. Is that gospel salvation? I don't think so.
In other words, it matters what you are hoping for through forgiveness. It matters why you want it. If you want forgiveness only for the sake of savoring the creation, then the Creator is not honored and you are not saved. Forgiveness is precious for one ultimate reason: it enables you to enjoy fellowship with God. If you don't want forgiveness for that reason, you won't have it at all. God will not be used as currency for the purchase of idols.
Similarly, why do we want eternal life? One might say it's because hell is the alternative, and that's painful. Another might say it's because there will be no sadness there. Others might say their loved ones have gone there and they want to be with them. Others might dream of endless sex or food. Or they might seek more noble fortunes. In all these aims, one thing is missing—God.
The saving motive for wanting eternal life is given in John 17:3: "This is eternal life, that they know you the only true God, and Jesus Christ whom you have sent." If we do not want eternal life because it means joy in God, then we won't have eternal life. We simply kid ourselves that we are Christians if we use the glorious gospel of Christ to get what we love more than Christ. The "good news" will not prove good to any for whom God is not the chief good.
Here is the way Jonathan Edwards put it in his sermon "God Glorified in Man's Dependence," which he preached in 1731. Read this slowly and let it waken you to the true goodness of forgiveness and life.
The redeemed have all their objective good in God. God himself is the great good which they are brought to the possession and enjoyment of by redemption. He is the highest good, and the sum of all that good which Christ purchased. God is the inheritance of the saints; he is the portion of their souls. God is their wealth and treasure, their food, their life, their dwelling place, their ornament and diadem, and their everlasting honor and glory. They have none in heaven but God; he is the great good which the redeemed are received to at death, and which they are to rise to at the end of the world. The Lord God, he is the light of the heavenly Jerusalem; and is the "river of the water of life" that runs, and the tree of life that grows, "in the midst of the paradise of God." The glorious excellencies and beauty of God will be what will forever entertain the minds of the saints, and the love of God will be their everlasting feast. The redeemed will indeed enjoy other things; they will enjoy the angels, and will enjoy one another: but that which they shall enjoy in the angels, or each other, or in anything else whatsoever, that will yield them delight and happiness, will be what will be seen of God in them.
The gospel is ultimately about God. He alone is the author and goal of salvation. The good news of John 3:16 is that God is the chief end of the gospel. He so loved the world not simply to give us forgiveness or eternal life but to give us something even greater—Himself.