“Jesus sternly ordered them
Not to make him known.”
καὶ πολλὰ ἐπετίμα αὐτοῖς ἵνα μὴ αὐτὸν φανερὸν ποιήσωσιν.
Mark said that Jesus strictly or sternly ordered, rebuked, chided, warned or admonished these unclean spirits (καὶ πολλὰ ἐπετίμα αὐτοῖς) that they should not make it known that he was the Son of God (ἵνα μὴ αὐτὸν φανερὸν ποιήσωσιν). This warning about the messianic secret can be found in all 3 synoptic gospels. Jesus, in some ironic way, did not want the people to know that he was the Messiah, the Christ, or the Son of God. Thus, the name “Jesus Christ” did not take hold until after his death and resurrection. Only these unclean spirits and a few elite followers of Jesus knew that he was the Christ messiah, the Son of God, much like a gnostic special knowledge. Somehow, Jesus had power over these unclean spirits.