Whenever anyone suggests the possibility of rejecting Paul, instantly the “orthodox” will defend him with an assertion something like:
Without Paul we’d believe we had to live a perfectly sinless life to be saved.
Now, that’s an absurd claim considering the only person in the biblical period who ever taught that God requires sinless perfection was Paul himself. You certainly don’t get this impression from Jesus.
Jesus taught “Blessed are the merciful for they shall obtain mercy.”
Jesus taught that we can pray for forgiveness and be forgiven if we forgive others.
Jesus taught that the angels in heaven rejoice over one sinner who repents.
Jesus taught in the parable of the prodigal that even if we left God and squandered our spiritual inheritance in a far country, when we come to our senses, we can come back and God will welcome us with open arms.
Jesus also taught that he that breaks the least of the commandments will be called least in the kingdom (but apparently still make it to the kingdom).
So, we clearly don’t get the impression from Jesus that sinless perfection is required for salvation. So without Paul, we know that salvation doesn’t require living a perfect life.
Now, if that’s what we mean by “grace”—i.e. God’s mercy in forgiving us—then Jesus taught it, despite not using the term “grace.”
If we means something else by “grace”—like Calvinistic magic enabling power to undo a total inherited disability and enable you to believe—then no, we can’t get that without not only Paul but Augustine too.
But look, the fact of the matter is that without Paul, we have a much more gracious gospel. Jesus never teaches that obedience undoes grace. Jesus never teaches that if we obey God (i.e. “works”) that we lose God’s mercy. Paul, however, seems to teach this. Paul insists that if any works are involved “then is grace no longer grace.” In the end, that becomes a sort of anti-obedience legalism, or antinomian legalism. It results in the idea that if you obey even one commandment once, you’ll be damned. So ultimately people come up with the idea that to be saved according to Paul, you must rely so heavily on faith and grace alone that you never obey God at all ever. Now, Jesus did not teach such a nightmarish doctrine!
Rather, Jesus clearly shows how grace (i.e. God’s mercy) and works work together.
“Blessed are the merciful, for they shall obtain mercy.”
Your merciful works help you obtain mercy.
“Pray: Forgive us our debts as we forgive our debtors.”
Your forgiveness of others helps you be forgiven.
“The angels in heaven rejoice over one sinner that repents.” The prodigal “came to himself and said ‘I will go home to my Father’s house!'”
Repentance and returning to God helps you obtain mercy.
Very different from Paul’s evil anti-works anti-law anti-obedience legalism.