But how much faith is necessary?

It is better to ask what sort of allegiance than how much, because allegiance depends on what Jesus the king commands each of us individually to do and whether he determines now and at the final judgment that you and I have given pistis. If we give pistis to Jesus as Lord by declaring allegiance, determining to enact loyalty, and showing through bodily doing that our determination was not just lip service, then we can rest assured that his death on our behalf is utterly and completely efficacious—all of our sins are forgiven in the Messiah (even our selfish acts of temporary disloyalty). And the Holy Spirit invariably comes alongside us to assist us in faithful living.—Matthew Bates in Salvation by Allegiance Alone, 124–25 (emphasis original)