Does the noble eightfold path fits a lay life perfectly? Or is there any part of it that cannot be followed/accomplished by a lay buddhist?
If that's the case, what part(s) doesn't have fit with lay life?
There is nothing in the above which a lay person cannot develop or not reap benefits by developing.
Being a monk you have less responsibilities hence more time to practice. The key is to practice regardless of whether you are lay or a monk.
I started to read a book, The Buddha's Teachings on Prosperity written by Bhikkhu Basnagoda Rahula.
This book says:
The Pali canon was written and organized (sorted) by monks. The advice to laypeople is scattered (not organized) within the canon and therefore difficult to find.
Although scattered in the canon there is there lots of advice for laypeople: about behaving ethically, choosing a good/compatible wife/husband, having a good relationship, making decisions which aren't corrupted by anger or greed, etc.
This book does not mention the eight-fold path by name, nor does it make any mention of some of the elements of the eight-fold path. For example it mentions right effort, right knowledge, but does not mention concentration.
There is hardly any mention of meditation in the book, except that it's practised by the Buddha and by monks.
The book doesn't mention the four noble truths; although in my opinion, some applications of those truths might be present, for example the advice to laypeople includes cessation of old ways of thinking (stop clinging to the notion of "caste" for example), and living in the present with impermanence (which IMO might be examples of how to apply the third noble truth to secular life).
"Because renunciation grants a more stable form of happiness, this "happiness in detachment" or vimutti sukha is said to be "better". This is the happiness experienced by the Buddha himself and by his ordained disciples. With fewer duties, those who renounce worldly life find fewer hindrances to inner peace. Happiness in lay life, on the other hand, fluctuates constantly because of the numerous conflicts and burdens inherent in that life. But other than this since comparison, which does indeed raise spiritual happiness above worldly happiness, no evidence suggests that the Buddha found fault with secular life or the happiness associated with it."
The purpose of the (ordained) Sangha is to be a highly dedicated and qualified community to take the Buddha's message to society:
Impermanence, dissatisfaction with worldly pleasure, and detachment from secular life served predominantly to train and maintain this community.
There is no evidence in the Nikayas, the most authenticated collections of the Buddha's teachins, that he appealed to his lay followers to meditate on impermanence or dissatisfaction.
It even says,
Further, almost every translator of suttas rendered the recurrent keyword dukkha as "suffering," and had readers believing that the Buddha regarded worldly life as miserable. However, dukkha indicates the insatiable nature of the human mind, not merely so-called suffering. The Buddha employed this word for the purpose of directing the bikkhus toward nibbana -- and not for the instruction of his lay disciples.
The book says a lot more than this; the above is a summary.
The last chapter of the book recommends the following as a path to lasting happiness:
Avoid mind-created reactions to everyday experiences
The Madhupindika Sutta explains that we attach meaning to sensory experience, allowing such thoughts to attack oneself.
Let go of greed and malice
Pursue a goal and enjoy achieving it
This type of happiness is called atthi sukha: especially, achieving a worthwhile goal.
Look at others' unpleasant actions with compassion
Work for others' benefit
Live a principled life
Accept the inevitability of change as natural law.
Wkipedia's Householder (Buddhism) article says,
In southeast Asian communities, lay disciples also give alms to monks on their daily rounds and observe weekly uposatha days. In Buddhist thought, the cultivation of ethical conduct and dāna or "almsgiving" will themselves refine consciousness to such a level that rebirth in one of the lower heavens is likely even if there is no further Buddhist practice. This level of attainment is viewed as a proper aim for laypersons.
IMO "cultivating ethical conduct" is good but it's not like full-time meditation. If laypeople aim for rebirth in one of the lower heavens then maybe, I suppose, they aren't hoping to become enlightened in this life.
It also says,
In some traditional Buddhist societies, such as in Burma and Thailand, people transition between householder and monk and back to householder with regularity and celebration as in the practice of shinbyu among the Bamar. One of the evolving features of Buddhism in the West is the increasing dissolution of the traditional distinction between monastics and laity.
In the Pali canon, the pursuit of Nibbana (Skt: Nirvana) within this lifetime usually starts with giving up the householder life. This is due to the householder life's intrinsic attachments to a home, a spouse, children and the associated wealth necessary for maintaining the household.
That whole Wikipedia article is worth reading carefully.
A simple question. A simple answer: Of course it can! It's as simple as this:
Each and every petal deserves a book of explanation but here I have simplified the structure. The Eightfold path is beneficial and good to follow for anyone! Be it ghost, layman, scientist, murderer, etc.
The only thing that is exclusive about lifestyle choices is Right Action and Right Livelihood. Depending on what school one is devoted to, it can be more strict or loose. The basic idea is that you do actions and take on a livelihood that does no harm to yourself or others! Simple enough to try, no?
Without those two exclusive choices, everything about the Buddhist path, the Eightfold path, is a path of golden behavior based on scientific principles including karma and reincarnation which are definitely "real" things.
Hope this helped.
Judging by the early texts and some of later teachers (e.g. Ajaan Lee), celibacy is a key factor, so it depends on what you take lay life to be. I imagine your question is not just philosophical, but, if put in practical terms would be: "What do I have to change in order to be practicing rightly as a lay follower?"
The problem, I believe, is that this depends a lot on your own individual personality and tendencies. The best thing to do would be to consult a teacher you trust. Feeding off the hive mind, even in its Buddhist sections, is probably not the best solution here. There's a known expression you might wish to consider every now and then about stuff like this: "a blind man leading a group of blind men." You want to make sure you're led by someone who can see.
Ajaan Mahā Boowa replied that in order to teach others, one must first clearly know the Dhamma for oneself. For the most part, he considered that those who had yet to see the true nature of Dhamma were unqualified to speak about it in front of other people.
Speaking of Ajaan Maha Boowa, you should have a look at the book
Ācariya Mahā Boowa in London available in several formats, for free, here. It's a translated transcription of several talks and Q&A sessions he gave to lay followers in London back in 1974.
No. As long as one clings to home and house (even Monks may make their status and monastery, lineage... their home) one is incapable even to reach the path, not to speak about the highest attaining.
If one is not able to leaves home, house, outwardly, how could he/she ever let go of the senses inwardly? How could he/she ever hear, read the Dhamma having reached a borderland of the Noble Domain?
So possible good to leave home and get familar of Where and what to practice?, leaving householder, outer lands domain, here and look after a far destiny where it could be found.
Wise if investigate whether ones informations are given by householder or those having gone forth, for how much faith and knowlegde could a to-house-returner have into Buddha, Dhamma, Sangha? Something many should think about, if capable and for their own benefit, if really desiring freedom from suffering.
[Note: This gift is not given for trade, exchange, stacks or Buddh-ism binding one to the house, home, but for leaving it beyond]