Of the two genealogies of Jesus given in the Gospels, Matthew mentions Solomon, but Luke does not. Some commentators see this as an issue that can be reconciled while others disagree. For instance, it has been suggested that Matthew is using Joseph's genealogy and Luke is using Mary's, but Darrell Bock states that this would be unprecedented, "especially when no other single woman appears in the line". Other suggestions include the use by one of the royal and the other of the natural line, one using the legal line and the other the physical line, or that Joseph was adopted.