Bible says eternal life is the reward of our faith. So faith (Christianity) contains the promise of a reward. A benefit. I agree doing good things is beneficial, but you don't need to be a Christian to do good things. Anyone can do that. But a non-Christian's reward is found in this life and that's as far as it goes. A Christian's is found in the next.
Except eternal life isn't a reward. And treating it like it's the reward for having picked the right set of religious beliefs presents Christianity as largely arbitrary and God as rather capricious.
Eternal life isn't a reward, it's God's purpose for creation. When God made all things He made them "exceedingly good" and made all things with purpose, goodness, and permanence--for life.
That's why St. Paul says the final enemy is death.
Because death, sin, etc is no impediment to God's good purposes; He is Creator and Redeemer. Redeeming that which He has made--that's salvation.
What God did for Jesus God is going to do for the whole world. That is why St. Paul in Romans ch. 8 says, "If the Spirit of Him who raised Christ up from the dead dwells also in you, then He who raised Christ from the dead will also give life to your mortal bodies." (Romans 8:11)
It is the hope of resurrection, and the renewal and healing of all creation that is the Christian hope.
That's not reward, that's God's good purpose.
The day will come when Christ returns, the dead shall be raised, and there will be judgment of the living and the dead; and God will make all things new.
History has conclusion, the present age will come to a close.
Entropy
does not win.
God wins. God has won in Christ, and God's victory in Christ is for all. Thus in the final analysis, after all enemies lay subject under Christ's feet, God will be all in all.
It's not "Christians go to heaven, non-Christians go to hell."
It's God is going to marry heaven and earth together in the end, and God will be all in all, and all of creation renewed and healed in Him shall enjoy the absolute fullness of life forever. Unto the ages of ages, forever and ever, world without end. We who have put our faith in Christ have hope of that, as we have the promises of God that we have been reconciled to God, our sins are forgiven, and the gift of the Holy Spirit is the guarantee--the "down payment" as it were--of that reality.
So what of hell? Not a punishment, but if the above is what God is all about and what God is doing, hell can rightly be called "not that".
To quote C.S. Lewis,
"
It's not a question of God 'sending' us to Hell. In each of us there is something growing up which will of itself be Hell unless it is nipped in the bud." - C.S. Lewis, God in the Dock
-CryptoLutheran