The first question:
Do wisdom and understanding increase gradually or do they come as explosions?
Understanding never comes, neither as a sudden phenomenon nor as a gradual one, because it is always there. You have it right now. It is not going to happen somewhere in the future. You are carrying it within you, just as a seed carries the tree, a woman carries a child. You are carrying it right now. Now it depends on you: if your intensity is total you will achieve it suddenly; if your intensity is not total you will achieve it by and by, in steps. But understanding never comes to you – you are understanding. Enlightenment is not something that happens to you – you are enlightenment.
Remember this; then it is a choice, your choice. If you desire it totally, in that fire of total desire all that covers that understanding burns; suddenly the light is there. But it is up to you. It is not part of the nature of enlightenment to happen gradually or to happen suddenly.
Don’t throw off the responsibility; that’s how people create philosophies and schools. In Japan two schools of Zen exist: one believes in sudden enlightenment, another believes in gradual enlightenment – as if these are the qualities of enlightenment, as if they belong to enlightenment. They don’t belong to enlightenment. Enlightenment is always there; it is for you to choose. If your desire is total not even a single moment is lost. But if your desire is not total it means that you yourself are not willing it to happen right now. You want to postpone it, you want it tomorrow, some other day. Then you go on playing tricks.
If you are really sincere there is no time gap, it can happen this very moment. Not even a single moment is to be lost, because it is already the case. One has just to look within. But if you don’t want it right now then you can wait for millennia.
I would like to tell you an old story. It happened in Ceylon:
There was a great Buddhist master who taught his disciples for almost eighty years. When he was a hundred and twenty he said one day, “Now, I am going to die after seven days.” So thousands of his disciples gathered for his last darshan, to see him for the last time.
The old man, before closing his eyes and dissolving withinwards, asked them, “Does somebody want to accompany me? If somebody wants nirvana, enlightenment, right now, then he should simply raise his hand and that will do.”