St. Paul was concerned about people deceiving other people away from the simplicity that is in Christ. All (or at least most) denominations of the Christian church have made salvation in Christ a little more complicated.
Rather than draw attention to all of these complications, I thought I would go through the Gospel with simple, biblical words.
God is love.
God so loved the world.
The world was the object of His love.
The expression of His love is giving.
What He gave was His only-begotten Son.
He gave what was most valuable to Him.
Sin came into the world through man.
All men have sinned.
The soul that sins shall die.
The son of God died for sinful man.
The son of God rose from the dead to justify sinful man.
The sinful man who believes in the Son of God is saved.