What is meant by his ‘coming on the clouds’ and ‘every eye seeing him’?

Rev. 1:7: “Look! He is coming with the clouds, and every eye will see him, and those who pierced him; and all the tribes of the earth will beat themselves in grief because of him.” (Also Matthew 24:30; Mark 13:26; Luke 21:27)

In what sense will ‘every eye see him’? They will discern from events on earth that he is invisibly present. Also referring to sight that is not physical, John 9:41 reports: “Jesus said to [the Pharisees]: ‘If you were blind, you would have no sin. But now you say, “We see.” Your sin remains.’” (Compare Romans 1:20.) Following Christ’s return, some persons show faith; they recognize the sign of his presence. Others reject the evidence, but when Christ goes into action as God’s executioner of the wicked, even they will discern from the manifestation of his power that the destruction is not from men but from heaven. They will know what is happening because they were warned in advance. Because of what is overtaking them, they will “beat themselves in grief.”

Who are “those who pierced him”? Literally, Roman soldiers did this at the time of Jesus’ execution. But they have long been dead. So this must refer to people who similarly mistreat, or ‘pierce,’ Christ’s true followers during “the last days.”—Matt. 25:40, 45.