And let not your behaviour be like that of this world, but be changed and made new in mind, so that by experience you may have knowledge of the good and pleasing and complete purpose of God.

For if their rejection [by God] meant that [the rest of] the world could be restored to favor [with God], what would [God's] receiving the Jews back into fellowship be, except like dead people coming back to life?

It is just like the way in which through one man sin came into the world, and death followed sin, and so death spread to all men, because all men sinned.