1 Cor. 15:2 says, “By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.” This is a different “if” than the one you explained in your article “What Does If Mean?” The “if” used here is primary article of conditionality. Can you explain the “conditionality” of this “if”?
In 1 Cor. 15:2 Paul was explaining that what he had taught them was the only way to be saved, and they had to remember that. Then he repeated the essentials of the Gospel. Christ died for our sins according to the Scriptures, He was buried and was raised on the third day, according to the Scriptures (1 Cor. 15:3-4). Reading on we learn that false teachers were saying there is no resurrection (1 Cor. 15:12) to which Paul replied that if there is no resurrection our faith is futile.
When Jesus went to the cross He took all of our sins upon Himself (Colossians 2:13-14). After the resurrection He went to sit at the right hand of the Father. God cannot be in the presence of sin, so if the crucifixion didn’t pay for all of our sins, Jesus could not have risen from the grave to be seated at the right hand of God. Therefore fact that He was resurrected is proof that all our sins have been paid for.
So if you don’t believe He was resurrected, then you can’t believe you will be. If you can’t believe you will be resurrected, you’re not saved and your faith is futile (1 Cor. 15:17).
Later Paul would write, “If you confess with your mouth, Jesus is Lord, and believe in your heart God raised Him from the dead, you will be saved” (Romans 10:9). True believers accept the resurrection of Jesus as fact. The conditionality of the “if” in 1 Cor. 15:2 is a warning that those who don’t believe in the resurrection are not saved.