15:21 This passage succinctly states one of Paul’s most profound teachings—our twofold solidarity with the first man, Adam, and with the last man, Christ. By virtue of our humanity, we are united with Adam in our present natural existence, in sin, and in death; by virtue of our faith, we are united with Christ in spiritual existence, in righteousness, and in the life to come (vv. 45–49; Rom. 5:17–19). See theological note “Resurrection and Glorification” on the next page.