15:21 Cyrene. Cyrene was an important city in what is today Libya. There was a large Jewish settlement in Cyrene going back several hundred years (Acts 6:9).

Alexander and Rufus. Simon’s sons may have been members of the Christian community to which Mark wrote, probably at Rome (cf. Rom. 16:13).

carry his cross. Usually the condemned man would carry the crossbeam, weighing thirty to forty pounds. Simon, in taking up the cross of Jesus, became a visual image of the true discipleship that Jesus demands (8:34).