1 Corinthians 15:3-4
3 For I delivered to you as of first importance what I also received, that Christ died for our sins according to the Scriptures, 4 and that He was buried, and that He was raised on the third day according to the Scriptures.
The most important thing about the Christian faith is the fact that Jesus came, He died, He was buried, and He rose again. This is the gospel, which Paul himself received, and that he had passed on to the Corinthians. The whole Christian faith relies on these facts. If Jesus never came or never died for our sins, or rose again, the Christian faith is worthless. Paul goes on in Chapter 15 to discuss this fact. We don’t believe in a good teacher (as some call Him), we believe in the Son of God, who died for our sins, paying our penalty and rose again 3 days later. Jesus, the perfect, sinless, Son of God took on my sin and your sin and died a cruel death, one which we deserve for ever and ever, in order that God the father, would consider our sins as forgiven.
Never doubt how far God went go to save you!