Gospel was preached in the form of the promises made to the Jewish fathers.
3.2 The seed of the woman in Gen. 3:15 refers to Christ and the righteous, who are and were temporarily 'bruised' by sin, the seed of the serpent.
3.3 In fulfilment of God's promises, planet earth will never be destroyed because the eternal inheritance of the earth was promised to Abraham, isaac and Jacob and their seed.
3.4 Abraham's and David's seed was Christ;
3.5 we can be in Christ by belief and baptism,
3.6 so that these promises have relation to the true believers