“I marvel that ye are so soon removed from him that called you into the grace of Christ unto another gospel: Which is not another; but there be some that trouble you, and would pervert the gospel of Christ. But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed. As we said before, so say I now again, If any man preach any other gospel unto you than that ye have received, let him be accursed. For do I now persuade men, or God? or do I seek to please men? for if I yet pleased men, I should not be the servant of Christ” (Galatians 1:6-10 KJV).
What is that Gospel?
“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” (I Corinthians 15:1-4 KJV).
Nothing about being baptized before a man is saved, it follows after . . . only.
However, there is a spiritual baptism that takes place as well as a circumcision.
“And ye are complete in him, which is the head of all principality and power: In whom also ye are circumcised with the circumcision made without hands, in putting off the body of the sins of the flesh by the circumcision of Christ: Buried with him in baptism, wherein also ye are risen with him through the faith of the operation of God, who hath raised him from the dead. And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses” (Colossians 2:10-13 KJV).
My only message to anyone seeking salvation by any other way than the death, burial and resurrection of Christ is . . . “I tell you, Nay: but, except ye repent, ye shall all likewise perish” (Luke 13:3, 5 KJV).
2 Thess 1:8 “In flaming fire taking vengeance on them that know not God, and that obey not the gospel of our Lord Jesus Christ:”
If one does not want to be lost in flaming fire, then one must obey the gospel of Christ.
As you point out from 1 Cor 15:1-4 that the gospel is the death, burial and resurrection of Christ.
Therefore if one must obey the gospel per 2 Thess 1:8 as to not be in flaming fire and the gospel is the death burial and resurrection of Christ per 1 Cor 15:1-4, then how does one obey the historical events of Christ’s death burial and resurrection?
Rom 6:1-7, when one is baptized into the death of Christ the old man of sin DIES, ones is “BURIED” from which one is “raised up from” - RESURRECTED. Therefore when one is water baptized there is a DEATH, BURIAL and RESURRECTION that takes place. At no other time or place does this death burial and resurrection take place.
Water baptism therefore is a FORM, an example, an outline of the gospel of Christ.....
Rom 6:17 “But God be thanked, that ye were the servants of sin, but ye have obeyed from the heart that FORM of doctrine which was delivered you.”
That “form” of doctrine those Romans had obeyed was water baptism, a death, burial and resurrection. Therefore the gospel and water baptism are interlinked together, inseparable. If one could be saved without the death burial and resurrection of water baptism then he could be saved without the death burial and resurrection of the gospel of Christ.
There is no death, burial and resurrection that takes place with faith only or in a “spiritual baptism” or by saying a sinner’s prayer but only in water baptism is the gospel of Christ obeyed as it must be to not be in flaming fire per 2 Thess 1:8.