There are three kinds of spirit spoken about in today's readings: the spirit of a person that knows the depths of a person, the unclean spirit that troubles a person and is cast out by Jesus, the Spirit of God that knows the depths of God. We need to consider all three if we are to understand ourselves fully.
Our own spirit shows itself in many ways: memory and imagination, anxiety and desire, our capacities for knowledge, understanding and love. The human spirit is seen in literature, art, music, technology, the whole panoply of activities and interests that make us to be very extraordinary animals indeed. In poetry and music, philosophy and theology, and many other ways, the 'spirituality' of the human creature is to be seen.
Unclean spirits are realities 'in us without us', we might say, that are known through their effects. As well as obvious external difficulties and obstacles, there are many ways in which human beings are afflicted and distracted from within. We continue to surprise and disappoint ourselves. 'I do not understand my own actions', Paul says in the letter to the Romans. Mean-spirited and selfish, hard-hearted and yet profoundly vulnerable, given to addiction and led by the opinions of various publics: there are many ways in which we are disturbed by the unclean spirits. Christian tradition has identified seven or eight deadly spirits or capital vices: vainglory, covetousness, lust, anger, gluttony, envy, sloth and pride.
But there is also the Spirit of God who finally reveals us to ourselves. In the first reading Paul says that the depths of God are accessible to the Spirit of God in something like the way the depths of a human being are accessible to the human spirit, but then says that actually the depths of ourselves are only now accessible to the Spirit of God and not to our own spirit. He is speaking of a new possibility, a new spiritual life, that is not simply part and parcel of the nature with which we were first created but that comes about through a new presence of the Holy Spirit in us. If we are to understand the gifts God has given us we need the Spirit of God. If we are to plumb the depths of ourselves it can only be with the help of the same Spirit.
This relativises our natural 'spirituality', placing its conflicts and achievements in a completely new light. There is a new world of wonder and admiration to which we are called. Paul speaks of new human beings who are capable of judging the value of everything, human beings who have 'the mind of Christ'. Natural spirituality is a token or intimation of what the Spirit brings. When the Spirit, the love of God, is poured into our hearts, not only are the unclean spirits put in their place but our capacities for knowledge, understanding and love are opened up to a new and truly transcendent objective, reaching even to God, in the supreme spiritual activities of faith, hope, and love.