....So what is the full Gospel? While it is summarized in 1 Corinthians 15:1-4, it needs to be expanded to explain what is being said: Moreover, brethren, I declare unto you the Gospel which I preached unto you, which also ye have received, and wherein ye stand; By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain. For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures; And that he was buried, and that he rose again the third day according to the scriptures:
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The gospel IS the power of God to salvation. However, there is more to the gospel message then what is specifically referenced in the scripture. (1 Corinthians 15)
"Moreover, brethren, I declare unto you the gospel which I preached unto you, which also ye have received, and wherein ye stand;
By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.
For I delivered unto you FIRST of all... "
Paul begins by reminding the group that he declared to them the gospel by which they were saved. (Verses 1-2) He goes on to point out a specific part of the gospel message that he and they received FIRST; that Jesus died for their sins, was buried and resurrected. (Verses 3-4) He then delves into concepts associated with resurrection throughout the remainder of the chapter.
Apostle Paul’s comment about Jesus’ death, burial and resurrection being what is shared with people FIRST indicates there is other information included in the gospel message. This truth is seen in scripture relevant to all groups of humanity; Jews, Gentiles and Samaritans. (Acts 2:22-41; 8:12-17; 10:37-48) In each of the referenced scriptures, individuals hear the word of God, repent as evidenced by a willingness to submit to water baptism in the name of Jesus, and become indwelt by the Holy Ghost as well. There are variations in the sequence of events, but all are noted.
Notice in 1 Corinthians 15 verse 29 Paul specifically brings up water baptism. Why bring it up if it is not part of the gospel message? He questions why people are getting baptized for the dead if they don't believe the dead will be resurrected. Even though baptism for the dead is not biblical it speaks to the fact that born again believers realized their own water baptism played a part in their spiritual rebirth. And as such, they were doing it in hopes of changing the fate of relatives and/or friends who had not submitted to it for themselves before meeting their demise.
Without a doubt, repentance and water baptism hold no significance without belief in Jesus’ death, burial and resurrection. Jesus’ sacrifice is what makes the NT spiritual rebirth possible in the first place. Even though Jesus died for the sins of all humanity, not all will have their personal sins washed away. It is through one's belief and obedience to God's plan of salvation as expressed in the word that all are given the opportunity to become born again children of God.