Christianity is all about God's search for mankind: it starts with God, not with us. Through Jonah, God went in search of the Ninevites, because he cared so deeply about their happiness. And the same thing happens in today's Gospel passage.

St. Mark shows Jesus doing what he came on earth to do: calling people into a personal relationship with God. That’s really the core of what Christianity is all about.

Notice how he calls his first Apostles by name.  He calls them, because he wants to give them more meaning, purpose, and, ultimately, happiness. This is what God is all about; he comes in search of every human heart, calling us into everlasting friendship with him.