Nothing is more central to the Bible than Jesus' death and resurrection. The entire Bible pivots on one weekend in Jerusalem about 2000 years ago. And it is as important to know and meditate on what these events mean as to know that they happened.
We are at all times challenged to stand firm in our faith in Jesus Christ. Our culture tries to intimidate Christians with accusations that we are backward or narrow-minded. How we react to these charges is an indication of our spiritual progress.
The gospel is not a narrow set of facts or mere formula to gain entrance to heaven. It is a broad category that holds much of the Bible together---taking people from alienation from God all the way through conversion and discipleship to the new heaven and earth.
There has to be an explanation why - despite millions who claim to be born-again Christians - the morals of America continue to decline, the young are abandoning their upbringing, and the public square is devoid of seriously-taken Christian voices.