1 Now I make known to you, brethren, the gospel which I preached to you, which also you received, in which also you stand, 2 by which also you are saved, if you hold fast the word which I preached to you, unless you believed in vain. 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,
– 1 Corinthians 15:1-4  

The above verse shows precisely the gospel (good news) that is believed in order to be saved. One must direct faith towards this gospel alone in order to be saved. Nothing can be added or taken away from this gospel.

The first aspect of this gospel is belief that Christ died for our sins. This is the death of God in the flesh not some ordinary man. It was Christ’s sinless human nature that satisfied God the Father’s outrage over man’s sin nature. In other words, the Son’s blood was sufficient for the redemption of man (Rom. 3:24-26). He didn’t die simply ‘for us’ but ‘for our sins’. His death saves the one believing from the guilt and penalty of their sins.

The second aspect was that Christ truly died. He suffered a physical death for our sins. What man has merited or deserved from the Righteous Judge is death. Christ paid that debt. The Bible informs the reader that just as working a job pays a wage, sin also pays a wage – death. Man is owed death for his work of sin. Christ paid that debt by physically dying on the cross.

The last aspect of the Gospel is that Christ rose again on the third day according to the Scriptures. The resurrection is crucial in proving that salvation is complete for the one believing. As Christ paid the penalty for man’s sins upon His death, so now those that believe are removed out from the unsaved state of death and placed into the Christ where there is eternal life.

One final point must be discussed. Notice that the basis of this salvation is upon a single condition – personal faith in the crucified and risen Son as an offering for sin. Since salvation is solely based on personal faith in Christ’s death for sins, the burial and Christ’s resurrection to life than it should be clear that it is not any work of man that merits salvation. It is a work of God on man’s behalf not a work of man on God’s behalf.

16 For I am not ashamed of the gospel, for it is the power of God for salvation to everyone who believes, to the Jew first and also to the Greek.  
– Romans 1:16

8 For by grace you have been saved through faith; and that not of yourselves, it is the gift of God; 9 not as a result of works, so that no one may boast. 10 For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand so that we would walk in them.  
– Ephesians 2:8-10

As explained in the verse above man’s salvation is a work of God (His workmanship). In order to even do the good works that God has prepared for believers to do, one must first be in Christ. This is accomplished at the moment one believes the gospel for salvation. It is then that the one believing is baptized (immersed or placed into) into Christ. It is from this position in Christ that the believer can live a life that is well-pleasing to the Father. The source of this life is not out from the believer’s own ability but from God as we abide in our position in Christ. Because Christ died and was raised to life, believers also have access to a quality of this resurrection life. The Bible calls this quality of life that is available in Christ – eternal life.

23 For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord.  
– Rom. 6:23