The word “Gospel” comes from the Greek word for “good news” and is a term that is used to refer to the message of Christianity.
The Gospel in a nutshell is that Jesus Christ came into the world to save sinners (a concept that comes from 1 Timothy 1:15). An accurate presentation of the Gospel must include the life, death, resurrection, and ascension of Jesus. In His life, Jesus taught His disciples in both word and deed (Mark 10:1; 1 Peter 2:21); in His death, He was the once-for-all sacrifice for our sins (Hebrews 9:28); in His resurrection, He defeated the power of sin and Satan (1 Corinthians 15:17); in His ascension, He sat down at the right hand of God where He now intercedes for us (Romans 8:34).
All four of those points are essential to understanding the work that Jesus performed in making salvation available to sinners.