In Romans 8 St. Paul points to two great truths which every true believer knows. The first (Verses 22,23) he knows by experience; the second (Verse 28) he knows by faith.
Rom.Β 8:22,23: βFor we know that the whole creation groaneth and travaileth in pain together until now. And not only they, but ourselves also, which have the firstfruits of the Spirit, even we ourselves groan within ourselves, waiting for the adoption, to wit, the redemption of our body.β
The words βuntil now,β in this passage, are significant, for our Lord came to earth healing the sick, cleansing the lepers, making the blind to see, the deaf to hear and the lame to leap for joy. But He was rejected by sinful men and nailed to a cross.
After His resurrection and ascension His persecutors were given another chance, however, as Peter called upon them to repent so that βthe times of refreshingβ might still βcome from the presence of the Lordβ (ActsΒ 3:19,20). But again the King and His blessed kingdom were rejected so that, in the words of Paul, the whole creation continues to groan and travail in pain βtogether until now.β
But in this passage the Apostle points out that even Godβs children are not exempt from this suffering, for the most sincere believer, the most consecrated saint, must still partake of the sufferings and sorrows of the world while he waits for βthe redemption of our body,β when βwe shall all be changedβ (I Cor.Β 15:51).
But while every believer knows about suffering and sorrow by experience, there is something else he knows by faith. Verse 28 speaks of this:
βAnd we know that all things work together for good to them that love God, to them who are the called according to His purpose.β
The true Christian is not a mere optimist; he is a believer in Godβs Word. source
