How can one become enlightened in one single moment? One can, because one is enlightened -- one just has to recognize the fact. It is not something that happens from the outside, it is something that arises from the inside. It has always been there but you were clouded, you were full of thoughts.
Do not think that enlightenment is going to make you special, it's not. If you feel special in any way, then enlightenment has not occurred. I meet a lot of people who think they are enlightened and awake simply because they have had a very moving spiritual experience. They wear their enlightenment on their sleeve like a badge of honor. They sit among friends and talk about how awake they are while sipping coffee at a cafe. The funny thing about enlightenment is that when it is authentic, there is no one to claim it. Enlightenment is very ordinary; it is nothing special. Rather than making you more special, it is going to make you less special. It plants you right in the center of a wonderful humility and innocence. Everyone else may or may not call you enlightened, but when you are enlightened the whole notion of enlightenment and someone who is enlightened is a big joke. I use the word enlightenment all the time; not to point you toward it but to point you beyond it. Do not get stuck in enlightenment.
The outer is easier, and the outer is objective. For example, one man, Thomas Alva Edison, discovers electricity and the whole of humanity uses it; there is no need for everyone to discover it again and again. Inner growth is a totally different phenomenon. A Gautama Buddha may become enlightened, but that does not mean that everybody else becomes enlightened. Each individual has to find the truth for him or herself.
When I did a therapist education in USA 1984, one of the course leaders - who had given personal and spiritual guidance to thousands of seekers of truth from all over the world, and who I consider to be one of the best spiritual therapists in the world - said that I was going to get enlightened, that I would 'disappear into the silence'. I did not really understand what he meant then, and it was totally absurd for me when other course participants congratulated me afterwards. The thought that I was going to be enlightened was totally absurd for me. For me enlightenment was something that happened to special and chosen persons like Osho, Buddha, Jesus, Lao-Tzu and Krishnamurti. I did not feel either special or chosen. I did not feel worthy of being enlightened.
Swami Dhyan Giten
When you continuously know and sense yourself as the space of consciousness rather than what appears in consciousness - sense perceptions, thoughts, emotions - then it can be said that you are enlightened... except that you wouldn't think or speak of yourself as 'enlightened', because that would instantly create another mind-based conceptual identity and so it would be the end of 'your' enlightenment.
Strictly speaking, "you" cannot become enlightened, because who you take yourself to be is like a ripple in the ocean of consciousness - or a little wave if you're a VIP - and the ripple doesn't become enlightened until it realizes that its ripple-identity is ultimately a misperception, that it is the ocean taking on a fleeting ripple-form.
...angels... are always being filled full of light, becoming ever more radiant and making blessed use of their natural ability to change. They dance for joy around the First Light, look continuously towards Him and are enlightened directly by Him, as they tirelessly sing the praises of the Fount of light and, being ministers of light, transmit illuminating grace to those lower beings who are being enlightened.
An enlightened awareness is within each one of us, right at this moment. This enlightened awareness is truly unborn and marvellously illuminating; and everything is perfectly managed by it. Conclusively realise that what is unborn and illuminating is truly awakened and without effort, rest naturally as the Unborn Mind. Resting in this way, you are a living Buddha.
One of the great images to come down to us through Zen Buddhism is the encounter between an enlightened master and an advanced apprentice during the course of a shared meal. The apprentice, becoming fed up with the stress and waiting and the master's apparent disregard for him, demands an explanation without complication of exactly how to become enlightened. The master asks, 'Have you finished your rice?' 'Yes,' says the apprentice. 'Then go wash your bowl.
Most people think that an enlightened Buddhist Teacher is a fireman; His job is to put the fire out so that you can live in your home safely. But seeker beware! A fully enlightened Buddhist teacher is an arsonist! His job is to set your spirit on fire...by feeding the flames of your soul with love.
To be informed is to know simply that something is the case. To be enlightened is to know, in addition, what it is all about: why it is the case, what its connections are with other facts, in what respects it is the same, in what respects it is different, and so forth. This distinction is familiar in terms of the differences between being able to remember something and being able to explain it. If you remember what an author says, you have learned something from reading him. If what he says is true, you have even learned something about the world. But whether it is a fact about the book or a fact about the world that you have learned, you have gained nothing but information if you have exercised only your memory. You have not been enlightened. Enlightenment is achieved only when, in addition to knowing what an author says, you know what he means and why he says it.
Mortimer J. Adler