Jesus truly does promise that “a faith as small as a mustard seed” will achieve something impossible and absurd, something unprecedented and unthinkable. But it is not a matter of either “exceptional deeds” or the “miracles” and “exceptional gifts of the Spirit” expected by those who chase after sensations. The most radical expressions of faith – truly absurd and impossible, indeed foolish and crazy in the eyes of “this world” – don’t look anything like that. They include forgiving when I could take vengeance, and even “loving my neighbour” and “turning the other cheek” when I have been done wrong to; giving away things that I could happily keep for myself; being generous above all to those who are unable to pay me back; giving up “for the sake of the Kingdom of God” something that others consider an essential part of a happy life, In the eyes of this world – and let’s face it, in our eyes too, depending on the extent to which we are part of it and influenced by its mentality – these are maybe even crazier, stranger, and even more unprecedented things than if a tree or a mountain shifted position merely by the power of the human word. If we have never had the feeling that what Jesus wants of us is absurd, crazy, and impossible, then we’ve probably either been too hasty in taming or diluting the radical nature of his teaching by means of soothing intellectualizing interpretations, or (mostly naïvely, illusorily, or even hypocritically) we have too easily forgotten just to what extent – in our thinking, customs, and actions – we are rooted “in this world” where totally different rules apply.
Tomáš Halík, Night of the Confessor: Christian Faith in an Age of Uncertainty, 26-27.