The Facts of the Gospel (15:1-4).
'Now I make known to you brothers, the gospel which I preached to you, which also you received, wherein also you stand, by which also you are saved, if you hold fast the word which I preached to you, unless you believed in vain.'
Paul has already emphasised the centrality of the cross (1 Corinthians 1:17-18; 1 Corinthians 2:2) and he now confirms it, along with emphasis on the resurrection, as ‘the Gospel' of Christ which he wishes now again to make known to them, the Gospel (Good News) which he had previously preached to them, and which they had received. It is also the Gospel in which they now stand and by which they are also being saved as long as they hold fast the word (of the cross) which he had preached to them. And that Gospel includes the resurrection of the body of Christ. It is the very opposite of what some of them are now saying.
'Now I make known to you, brothers.' The word 'brothers' is all embracing and includes 'sisters'. It refers to all. Paul especially uses it in this letter when what he is saying is controversial, here because many of the Corinthians clearly laid doubt on the bodily resurrection. Having dealt with many of their questions he now comes to deal with the central matter, the content of the true Gospel.
'The Gospel which I preached to you.' He is bringing them back to the Gospel which he had first proclaimed in Corinth, that Gospel which had been so effective among them.
'Which also you received.' He reminds them that then they had received it gladly. But it may also include the technical sense that they had 'received' what had been 'delivered' and therefore had a responsibility towards it. It was received from God.
'Wherein also you stand.' This Gospel is the stance on which the Corinthian church is founded, the basis of what they represent, and what they are now standing on against the world and the Devil. It includes the fact that they know that they have been justified by faith and stand firm in the grace of God (Romans 5:2; 1 Peter 5:12), and are protected from the Enemy's onslaughts by the truths of the Gospel and of the word of God (Ephesians 6:12-17).
'By which also you are being saved.' The present passive confirms that they are in the process of salvation, a process which is continual, and the passive indicates the source, that their salvation is of God. They are 'being saved' ones, and that by God, and that is because of their faith in this true Gospel that he is about to expound on.
'If you hold fast the word which I preached to you.' And yet that salvation is dependent on their holding fast to 'the word' that he had preached to them, that is 'the word of the cross' (1 Corinthians 1:17-18). That is where he began and that is where he will finish. Salvation lies nowhere else. That is the essence of the Gospel, and includes, as Paul now makes clear, the reality of the bodily resurrection of the Christ, and the hope of the resurrection for all who are His.
'Unless you believed in vain.' This means either that if they do not hold fast to it, it will be because they have believed in vain, or that the whole Gospel hangs together in such a way that unless in fact their belief in it has been in vain (which is clearly not true) it must all be held as one. They cannot pick and choose, for the Gospel not only consists of the cross, it consists of bodily resurrection.
He wants to bring them back to what had first brought them to Christ, so that they might consider the whole. That is why he now makes it known to them afresh. Let them recognise that in this is their hope. Without it they have no hope, whatever their professed spirituality. It is only if they stand in that Gospel that they are 'being saved', that God is doing His saving work within them. They must hold it fast, for in that alone are they eternally secure.