user157: The founder of the Triratna Buddhist Community, Sangharaskshita, stated that he thinks stream entry is realistic after twenty or thirty years

In fact, it would be surprising if, after 20 or 30 years of life in
  the Order, you were not a Stream Entrant. It would seem to be very
  surprising, if you have done all the other things - maybe you have
  founded Centres and written books and given so many lectures and gone
  on so many retreats, that you were not a Stream Entrant: why not?

It's obviously a very bold statement. Does anyone else give that kind of timescale for stream entry or do any modern traditions give any kind of timescale at all. Or is Sangharaskshita a complete outlier with this kind of estimation.
Note: Tiratna is my Sangha which I think is right to acknowledge in the question. That said it doesn't stop me finding some of Sangharaskshita's statements bold or even controversial and I'm always interested on outside perspectives on his statements.

user8157: The Pali scriptures report stream-entry occurs at the very moment that Right Understanding is perfected & applied (e.g. the stream entry of the monk Kondanna in SN 56.11 & the stream entry of the householder Upali in MN 56). 
MN 10 states full enlightenment can happen in 7 days therefore stream-entry obviously sooner.

Should any person practice these four foundations of mindfulness in this manner for a week, then one of these two fruits may be expected
  by him: highest knowledge here and now, or if some remainder of
  clinging is yet present, the state of non-returning.
MN 10


user13375: According to Mahayana Gelug school of Tibetan Buddhism stream entry occurs with the first Bhumi or the Path of Seeing and is thus the demarcation between ordinary beings and Arya beings. I think this is an exceedingly rare realization in modern day and probably you could count on two hands the number of humans who have achieved this who are currently alive. Of course, I'm just an ordinary being so I really have no idea. I could be completely surrounded by Arya beings and not even know it :)

user745: That sounds very reasonable provided of course that the practitioner is keeping the 5 precepts, meditate a good amount each day, have studied enough to abandon wrong views, and are very consistent in their practice. I think in that case the biggest obstacle would be making sure that they are properly developing the quality of Vipassana in their meditation along side Samatha. If they can do that, then I think 20 or 30 years is quite realistic.

user10293: If you have enough belief in Dhamma and your meditation teacher, purified Sila(at least five precepts), relentless effort for insight meditation, you will surely get sustainable concentration to achieve stream-entry level wisdom in seven days . It was in the past, so is the same nowadays. It is the TRUTH.

user43: I kinda agree, 20 years should be enough if you are serious. The problem is, not many people are that serious, so it takes them longer. 

user5715: There are a number of Thera- and Therī-gāthā poems which feature men and women with many years experience and no realisation.
Anon (Thī 67-71) begins:

paṇṇavīsativassāni, yato pabbajitā ahaṃ.
nāccharāsaṅghātamattampi, cittassūpasamajjhagaṃ.
25 rainy season since I went forth and,
Peace of mind has eluded me, even for a finger snap.

Also Sāmā (Thī 39-41) and so on.

user715: I think one would find it nearly impossible not to gain stream entry if they've been observing their emotions and reality for two or more decades. I'm even inclined to take the Buddha's estimate of 7 days and nights to a maximum of 7 years to gain arhatship on face value. 
I don't think it's that difficult, most people spend 15 years studying hard to become a surgeon. We live in times of prosperity where people can afford to take that kind of time to better themselves that would have been impossible 2600 years ago without making huge sacrifices. 
Sure there are more distractions today, but if someone put in similar effort, arhatship should be possible. Modern society largely lacks appreciation for the goals of arhatship and that is the primary impediment.
Having said that, please see

AN 3.91: Accayika Sutta — Urgent {A i 239; Thai 3.93} [Thanissaro].
  Just as a farmer can't predict when the fruit will ripen, so we can't
  predict when Awakening will occur. So just keep your practice strong;
  the rest will take care of itself.


One maybe tempted to ask where are these numerous stream entrants or arhats if the western buddhist order practice leads to stream entry.
Speaking from the ultimate view, aspiring or even positing that there is a stream entrant or arhat after the event is Sakkāya diṭṭhi  or personality view. Since enlightenment is the loss of personality or realization of anatta, there can be no personage who is enlightened.
I like the the Zen terminology in this matter for its lack of confusion. There is only satori or kensho, but no person who is satoried.
I don't know why the Pali/Theravada terms are laden with the personality view, of a walking talking stream entrant / arhat as an individual.
I think it is an exercise in futility if one sets forth to find and interview an arhat. One might have better success sitting down and resolving to attain arhatship.

Dharma Talk by Ajahn Sumedho - Freedom can be Experienced but not Attained


user-1: It can be difficult to give an exact timescale since there are different factors involved in the practice, for each being. 
Some beings might have done extensive and concentrated practice in past lives allowing them to reach stream entry quickly in this life or future lives. 
Other beings might not have accumulated that kind of practice. All beings have different kamma. 
It might be dangerous to put a timescale on the achievement of stream entry since it takes one out of the present moment and into the future. It can also build expectations to the practice which can hinder ones progress. 
One might not solve all problems in this life or the next one but by practicing diligently one is altering ones habits towards goodness and these habits is what eventually leads us to enlightenment. If one does good things and practice diligently then the mind is inclined towards Nibbana. This means that when one is on the path it will eventually lead to liberation. Don't worry too much about when it's going to happen. 

157: <p>The founder of the Triratna Buddhist Community, Sangharaskshita, stated that he thinks <a href="https://thebuddhistcentre.com/system/files/groups/files/Bodhiketu-Stages-of-the-path.pdf" rel="nofollow">stream entry is realistic after twenty or thirty years</a></p>

<blockquote>
  <p>In fact, it would be surprising if, after 20 or 30 years of life in
  the Order, you were not a Stream Entrant. It would seem to be very
  surprising, if you have done all the other things - maybe you have
  founded Centres and written books and given so many lectures and gone
  on so many retreats, that you were not a Stream Entrant: why not?</p>
</blockquote>

<p>It's obviously a very bold statement. Does anyone else give that kind of timescale for stream entry or do any modern traditions give any kind of timescale at all. Or is Sangharaskshita a complete outlier with this kind of estimation.</p>

<p><strong>Note</strong>: Tiratna is my Sangha which I think is right to acknowledge in the question. That said it doesn't stop me finding some of Sangharaskshita's statements bold or even controversial and I'm always interested on outside perspectives on his statements.</p>
 8157: <p>The Pali scriptures report stream-entry occurs at the very moment that Right Understanding is perfected &amp; applied (e.g. the stream entry of the monk Kondanna in SN 56.11 &amp; the stream entry of the householder Upali in MN 56). </p>

<p>MN 10 states full enlightenment can happen in 7 days therefore stream-entry obviously sooner.</p>

<blockquote>
  <p><em>Should any person practice these four foundations of mindfulness in this manner for a week, then one of these two fruits may be expected
  by him: highest knowledge here and now, or if some remainder of
  clinging is yet present, the state of non-returning.</em></p>
  
  <p><em>MN 10</em></p>
</blockquote>
 13375: <p>According to Mahayana Gelug school of Tibetan Buddhism stream entry occurs with the first Bhumi or the Path of Seeing and is thus the demarcation between ordinary beings and Arya beings. I think this is an exceedingly rare realization in modern day and probably you could count on two hands the number of humans who have achieved this who are currently alive. Of course, I'm just an ordinary being so I really have no idea. I could be completely surrounded by Arya beings and not even know it :)</p>
 745: <p>That sounds very reasonable provided of course that the practitioner is keeping the 5 precepts, meditate a good amount each day, have studied enough to abandon wrong views, and are very consistent in their practice. I think in that case the biggest obstacle would be making sure that they are properly developing the quality of Vipassana in their meditation along side Samatha. If they can do that, then I think 20 or 30 years is quite realistic.</p>
 10293: <p>If you have enough belief in Dhamma and your meditation teacher, purified Sila(at least five precepts), relentless effort for insight meditation, you will surely get sustainable concentration to achieve stream-entry level wisdom in seven days . It was in the past, so is the same nowadays. It is the TRUTH.</p>
 43: <p>I kinda agree, 20 years should be enough if you are serious. The problem is, not many people are that serious, so it takes them longer. </p>
 5715: <p>There are a number of Thera- and Therī-gāthā poems which feature men and women with many years experience and no realisation.</p>
<p>Anon (Thī 67-71) begins:</p>
<blockquote>
<p><em>paṇṇavīsativassāni, yato pabbajitā ahaṃ.<br />
nāccharāsaṅghātamattampi, cittassūpasamajjhagaṃ</em>.</p>
<p>25 rainy season since I went forth and,<br />
Peace of mind has eluded me, even for a finger snap.</p>
</blockquote>
<p>Also Sāmā (Thī 39-41) and so on.</p>
 715: <p>I think one would find it nearly impossible <strong>not</strong> to gain stream entry if they've been observing their emotions and reality for two or more decades. I'm even inclined to take the Buddha's estimate of 7 days and nights to a maximum of 7 years to gain arhatship on face value. </p>

<p>I don't think it's that difficult, most people spend 15 years studying hard to become a surgeon. We live in times of prosperity where people can afford to take that kind of time to better themselves that would have been impossible 2600 years ago without making huge sacrifices. </p>

<p>Sure there are more distractions today, but if someone put in similar effort, arhatship should be possible. Modern society largely lacks appreciation for the goals of arhatship and that is the primary impediment.</p>

<p>Having said that, please see</p>

<blockquote>
  <p><a href="http://www.accesstoinsight.org/tipitaka/an/an03/an03.091.than.html" rel="nofollow">AN 3.91: Accayika Sutta — Urgent {A i 239; Thai 3.93} [Thanissaro]</a>.
  Just as a farmer can't predict when the fruit will ripen, so we can't
  predict when Awakening will occur. So just keep your practice strong;
  the rest will take care of itself.</p>
</blockquote>

<hr>

<p>One maybe tempted to ask where are these numerous stream entrants or arhats if the western buddhist order practice leads to stream entry.</p>

<p>Speaking from the ultimate view, aspiring or even positing that there is a stream entrant or arhat after the event is <em><a href="http://www.wisdomlib.org/definition/sakkaya-ditthi/index.html" rel="nofollow">Sakkāya diṭṭhi</a></em>  or personality view. Since enlightenment is the loss of personality or realization of anatta, there can be no personage who is enlightened.</p>

<p>I like the the Zen terminology in this matter for its lack of confusion. There is only satori or kensho, but no person who is <em>satoried</em>.</p>

<p>I don't know why the Pali/Theravada terms are laden with the personality view, of a walking talking stream entrant / arhat as an individual.</p>

<p>I think it is an exercise in futility if one sets forth to find and interview an arhat. One might have better success sitting down and resolving to attain arhatship.</p>

<ul>
<li>Dharma Talk by Ajahn Sumedho - <a href="http://www.amaravati.org/audio/freedom-can-be-experienced-but-not-attained/" rel="nofollow">Freedom can be Experienced but not Attained</a></li>
</ul>
 -1: <p>It can be difficult to give an exact timescale since there are different factors involved in the practice, for each being. </p>

<p>Some beings might have done extensive and concentrated practice in past lives allowing them to reach <em>stream entry</em> quickly in this life or future lives. </p>

<p>Other beings might not have accumulated that kind of practice. All beings have different kamma. </p>

<p>It might be dangerous to put a timescale on the achievement of <em>stream entry</em> since it takes one out of the present moment and into the future. It can also build expectations to the practice which can hinder ones progress. </p>

<p>One might not solve all problems in this life or the next one but by practicing diligently one is altering ones habits towards goodness and these habits is what eventually leads us to enlightenment. If one does good things and practice diligently then the mind is inclined towards Nibbana. This means that when one is on the path it will eventually lead to liberation. Don't worry too much about when it's going to happen. </p>
