Thursday of week 2 in Ordinary Time
This is also an optional memorial of St Fabian, Pope and Martyr
A frequent theme in the Gospel of Mark (and not exclusive to it) is the messianic secret - Jesus wishes for no one to speak of him as the Son of God. What does that phrase mean? The title Son of God is (in Hebrew) reserved to those who exercise, or substantiate the will and power of God. So the unclean spirits, yielding to the power in Jesus, naturaly might refer to him by that title. The Title also refers to Israel, God's beloved son, that he cherished - the people of God. At this point in the Gospel, the time is not yet ripe for Jesus to be proclaimed as both the saving redemptive power of God, and his Beloved son the King of this people.
Taken as an isolated incident, each casting out can be seen as the power of God working through this man Jesus - the Son of God meaning power - but taken in their totality the Gospels point unerringly to Jesus as the beloved Son and as our beloved King, the Messiah.