Vanity is like smoke or wind - it all vanishes. Nothing is of much value or importance. One person can labor for a lifetime and when that person dies, the profits and accumulations might be given to one who did nothing to deserve it all.
The gospel today makes a lot of sense. It points at how we can get caught up in what we own and what people have. It's about possessions and how they take us over. Or how we react when we lack what we once had.
The parable is meant to remind us all that life is short and fragile and what matters to God has to do with God's greater plan for the human race.
St Ignatius mentioned three obstacles to our faith - wealth, honour, pride. He saw from his own experience that people wanted wealth so that they would be highly thought of - it can be right school, the right address, the right bank. And we know things can change very quickly. Shares may go down, you may die or become ill and what then?
What we have is gift, given to us for the good of the world, the community, the neighbourhood, not just for the good of myself. The parable is meant to remind us all that life is short and fragile and what matters to God has to do with God's greater presence within the human experience.
Be rich in God - in mercy, love, forgiveness and justice.