Christ did not achieve or establish the divine truths of the gospel, he did not alter the relationship between God and humanity. God’s love for sinners has always existed, God’s forgiveness of sins has never wavered or changed or grown: these were as much a part of the fabric of reality before the life, ministry and suffering of our Lord as they have been since. The doctrines of the resurrection and never-ending life with God were true before Jesus taught them. That’s why Jesus offered the summary of his work to Pilate in these words: For this cause I was born, and to this end came I into the world, that I should bear witness to the truth.
To bear witness. Not to establish or create. To bear witness to what is and has always been and always will be: the truth.
The same thing is meant by Paul writing to the Romans: But God commended his love towards us, in that, while we were yet sinners, Christ died for us.
The death of Christ was God commending his love towards us, showing his love. All that Jesus did was making God manifest. The reality that had been kept secret from the foundation of the world was made known when this sun of righteousness arose with healing in its rays, just as the rising sun in the east reveals that which had been hidden by the night.
Jesus did not abolish death; his resurrection made manifest the abolition of death.