As I read the first lines of today's Gospel, the part where Jesus said to Matthew "follow me" and Matthew got up and did so without a word, I thought of the contrast with the story of the rich young man which comes later in Matthew's gospel. Matthew the tax collector, a loan shark if you will, just gets up and follows and manages to attract other "low-lifes" as well. The rich young man attracts no one, and wrestles with his own issues.
The point is that sometimes we get to the point that we see that there really is nothing else other than what God promises us. Matthew had probably seen enough in his life to know that when he met Christ that this was "it." The rich young man wasn't there yet.
Which, of course, leads to, "where are we?"