Which section of the Bible contains the instructions for the Age of Grace we live in?

Les teaches that to get into the area where you and I live today, in this Age of Grace, there is only one section of your Bible that gives us all the instructions for it: Romans through Hebrews, the writings of Paul. He points out that Paul writes to the Corinthians, basically a Gentile congregation, so he can just as well be writing to you and I tonight. Les then cites chapter 5, verse 14, where Paul says the love of Christ constraineth us, because we thus judge that if one died for all, then were all dead; and that He died for all, that they who live should not henceforth live unto themselves, but unto Him who died and rose again. Les calls this Paul’s Gospel: that Christ died, was buried, and rose from the dead. He also explains that “Wherefore henceforth” means from this point on—Paul is not going back 40 or 100 years, but from his time on—and now we know Christ no more after the flesh.