Theology 1.0: What is the earliest Christian creed?

St. John Cathedral, Hong Kong in 2016

For what I received I passed on to you as of first importance: that Christ died for our sins according to the Scriptures, that he was buried, that he was raised on the third day according to the Scriptures, and that he appeared to Cephas, and then to the Twelve. After that, he appeared to more than five hundred of the brothers and sisters at the same time, most of whom are still living, though some have fallen asleep. Then he appeared to James, then to all the apostles, and last of all he appeared to me also, as to one abnormally born.
-- 1 Corinthians 15: 3 - 8

A creed is a statement of belief. The first Christian creed is found in 1 Corinthians 15: 3-8, stating that Jesus died and rose again. Paul is estimated to have written this creed 2 - 24 years after the crucifixion of Jesus.

The significance of this creed was that it was written so close to the actual events of Jesus's life that it would have been easy for the early Christians to correct Paul had he been inaccurate.

This creed lends credibility to the historical reliability to the New Testament.

For further details
Article from CARM

Article from Wikipedia