Jesus had been tortured by the temple guards, Herod’s guards, and the Romans before he was forced to carry the cross. He had not slept in more than 24 hours, not during his preaching and teaching in the temple the day before, not while he prayed on the Mount of Olives, and not during the trials. He was exhausted. The Roman guards, wanting to hurry the crucifixion, conscripted someone to carry the cross the rest of the way.
Simon may have become the first convert to Christ from Cyrene because of being forced to carry the cross. The fact that Mark (who was the youngest gospel writer) mentioned his sons, Alexander and Rufus, indicates that Simon’s sons were prominent in the early church. (Mark 15:21)
Simon probably wondered why God made him carry someone else’s cross. Later, he probably realized that through this, his sons would become Christians with an important place in the church. God works in ways we cannot comprehend, even through hardship.
