Who carried the cross? Mark 15 vs John 19

The passages

And they compel one Simon a Cyrenian, who passed by, coming out of the country, the father of Alexander and Rufus, to bear his cross.

Mark 15:21

And he bearing his cross went forth into a place called the place of a skull, which is called in the Hebrew Golgotha.

John 19:17

The problem

Matthew, Mark and Luke agree that a passer-by named Simon from Cyrene was pressed into carrying the cross. John, who gives a long and detailed account of the trial and crucifixion, does not mention Simon and says only that Jesus went out "bearing his cross". Read side by side, the two pictures are hard to hold at once.

What believers and scholars say

Jesus began, Simon finished. The common harmony is that Jesus carried the cross out of the city, collapsed or slowed, and Simon was then conscripted. Luke 23:26 says Simon carried it "after Jesus", which is consistent with a hand-off.

Compression in John. John often summarizes. He may have left out Simon because it did not serve his emphasis, which is Jesus as one who goes to his death in control of events. The omission is a literary choice, not a denial.

A theological adjustment. Some scholars suggest John altered the tradition on purpose. If the cross was carried by Jesus in John's telling, it fits John's portrait of a Jesus who is never overpowered. A few also note that Mark's naming of Simon's sons suggests they were known to his first readers, which gives the Synoptic detail some weight.

Where this leaves it

The simplest reading of each text conflicts with the other. A hand-off harmonizes them with a single assumption. Whether you take that assumption depends on how you read John's habit of shaping his material. It is a small difference in a narrative that agrees on the central fact that Jesus was crucified outside Jerusalem.