This is because what one has faith in or believes is not central to the practice of Buddhism. There is no real concept of sin, soul, deities or an afterlife, nor is there any special supernatural authority for its teaching.
Buddhism is fundamentally about who and what you are, how you live and the quality of your life. It is grasping the nature of existence and reality in the here and now. Your experience of what works is the bottom-line. We must each prove its truths personally. Nothing is to be taken for granted nor can any outside authority bestow its benefits. Only you can awaken yourself to its full realization. The aspects of Buddhism that cannot be so proven and demonstrated directly are just its trappings and ornamentation. While interesting, they are not directly relevant.
The Buddha was a guy who lived in what is now India twenty five hundred years ago. He was born a prince and had an overly protective dad. He married and had a son. Eventually he grew old and died of food poisoning. During his life he noticed that certain aspects of life obsessed him and diminished the overall quality of his experience. For example: sickness, old age, death, missing his loved ones, the company of jerks, war, greed, poverty, all the same ills that still bother us today. All of these things seem inevitable to him and his concern about them caused him great mental and spiritual anguish which he called suffering.
When he hit his midlife crisis he decided to see if he could figure out a remedy to this suffering he felt. He first tried what was recommended by the sages of his time: drowning his cares in sensual excess and the opposite extreme of complete asceticism.
He found that both of these approaches were unsatisfactory and seemed to leave the root of the problem untouched. So he decided upon a course of moderation and sat down under a tree to work out the problem for himself.
He concluded that he couldnít change the nature of reality and that even if he could, reality wasnít actually the problem. It wasnít what he actually had or didnít have which troubled him. The problem was that no matter how his life went, he constantly wanted it to be different in some way or he was distracted and lost in impossible fantasies of the past or future. Enough could be more; good could be better; and, letís have less awful in the world. Finally it hit him. It wasnít that reality was unsatisfactory. Reality was just reality. What made it unsatisfactory was that his desires were insatiable; he was clinging to impossible expectations; and, his mind was distracted and confused.
Here at last he found the source of his trouble. It was his own habits that lead him to insatiable desires, clinging, unreasonableness, distraction and confusion. These bad habits polluted his enjoyment of life and separated him from his experience of reality as it is.
Upon deep reflection he discovered his habitual creating and clinging to his own suffering stemmed from three basic mental failings. These failings were ignorance, fear/anger, and greed.
But just knowing this did not free him from them. They had become a pernicious set of bad habits that feed on their own energy.
To remedy these failings he found it necessary to cultivate six mental and spiritual strengths: generosity, joyful effort, patience, concentration, personal morality, and wisdom.
To help get this cultivation of mental and spiritual strength rolling he picked eight particular things to practice and five particular things to avoid.
The things he chose to practice were: clear understanding, correct reasoning, appropriate expression, helpful action, beneficial livelihood, sufficient effort and focused concentration.
The things he chose to avoid were: harming yourself or others, taking what is not given, sexual abuse, false expression and intoxicant abuse.
His choices were based solely on his understanding of human nature, how habits hold us, and how cause and effect work. It is important to realize that they are not holy mandates nor is there any one waiting to punish any one who strays or reward those who practice carefully. The reward of living in this way is just that oneís life experience is optimal regardless of oneís circumstances.
Now none of this is particularly novel. Buddhism has no monopoly on knowing how to lead a good life or gain insight. The basics have been generally understood and agreed upon for millennia. So, what is it that holds us back and keeps us from doing it every moment?
Knowing is not doing.
It is only when we actually put this knowledge into practice, pay attention to what happens, and discern what works from what doesnít work that these concepts become realization and awakening.
So what are the tools by which we can manifest this practice?
They are meditation, unconditional generosity, moderation and the company of good and like-minded friends.
Meditation is the tool that leads to insight into life and comprehension of the mind. It is just sitting and letting the mind become still and observant. As this is practiced the starting, ebb, flow and ending of thoughts and emotions will become apparent as will the understanding that such are the function of mind, but they are not mind itself.
Unconditional generosity is more than just being generous with oneís possessions. It is a basic generosity of spirit. A giving without let or want of oneself. By means of this generosity clinging to things is defeated and both friendliness and compassion are cultivated. Ultimately this is the means to know real joy and happiness. Moderation is choosing satisfaction over excess. By this choice the senses are neither cut off nor over indulged and the passions are controlled so we do not hold grudges against others and desires do not hold and control us.
Finally there is the company of good and like-minded friends. The benefit of such company goes beyond the immediately obvious benefits of companionship. They are your teachers, peers and students. They are a friendly reality check and inspiration along the way. And, ultimately they are the first real test, for while awakening and realization is innately personal, the expression of the deep understanding and compassion it brings is innately social.
Of course in the beginning everyone gets it wrong. Buddhism is must be learned and old habits sometimes die hard. But practice, paying attention and then discerning what works from what doesnít work is a virtuous loop which builds inexorably towards awakening and the guidelines that the Buddha laid down so long ago will keep one from too grave an error in the mean time.
That is the essence of Buddhism.
You may have noticed there is nothing here that couldnít be practiced by a non-Buddhist. That is why I said the essence of Buddhism is better characterized as a wisdom tradition than as a religion. The practice of this path is merely a means by which oneís life can be brought into focus and one can awaken into the full realization of the here and now.