user533: What is the Buddhist view on crying? I don't remember hearing or reading about the Buddha ever crying. Is crying a consequence of "lack of understanding" of the ultimate reality?

user7611: An enlightened person who has achieved arahantship has put an end to mental fermentations, so how would they cry?
Fermentations which would cause one to cry, experience grief and sorrow wouldn't be there. 
This means they could only pretend to cry or have the appearance of crying but not actually experience grief or sorrow.

"From craving springs grief, from craving springs fear. For one who is wholly free from craving there is no grief; whence then fear?" (Dhammapada, 216)



"Whoever is overcome by this wretched and sticky craving, his sorrows grow like grass after the rains."
"But whoever overcomes this wretched craving, so difficult to
  overcome, from him sorrows fall away like water from a lotus leaf."
  (Dhammapada, 335-336)

Nibbana is the highest bliss, highest enjoyment, with fermentations (asavas) put to an end how can someone cry, be fearful, sorrowful, angry? Experiencing such an extreme form of enjoyment why would anyone cry?
Doubtless, fearless, sorrowless, angerless, calm, and happy walks the arahant.

user715: 
What is the Buddhist view on crying?

We must not pretend to be the Buddha, if tears come, we must respect that while investigating causes and conditions, using the moment as a teacher, to gather fresh insight. When true understanding is born, the tears will naturally dry up. New tears of compassion may form as one walks the path of the Bodhisattva.
Bodhisattvas have cried at seeing the fate of those in pain, and enlightened people like Jesus have shed compassionate tears. 

I don't remember hearing or reading about the Buddha ever crying.

I can't recall any suttas that talk about the Buddha crying or not, but I am not a Tipitaka master. It is not explicitly one of the 18 Buddha attributes. One can surmise therefore that this is not considered a very important distinction.
The key aspect of a Buddha is volition. If he cried at all, it would not be meaningless. 

Is crying a consequence of "lack of understanding" of the ultimate
  reality?

Yes and no - Involuntary crying of the nature humans often perform - where we try to hold back our tears, yet the circumstance overpowers us should not be the case for the Buddha. He has no remaining sankharas, no hidden traumas in the mind, no lack of control over his actions and perfect understanding of cause and effect.
If his crying served a purpose, then he may cry because it is Upaya. 
Caveat: I am no Buddha, so I can't know for sure. It makes me a little uncomfortable to deal in the hypothetical.

user111: Crying can be caused due to both physical and mental reasons.
Physical reasons:

Irritation in the eyes.
Sickness affecting the eyes.
Side effects of strong medication or extremely spicy food.

Mental reasons:

Sadness(obvious sadness and the sadness disguised as compassion), depression, aversion to pain, fear
Clinging to happy/pleasant/joyful states of the mind.

Assuming that this question is aimed at the 2nd category, it is highly unlikely that a fully enlightened being would cry as they no longer become sad or cling to pleasant states of the mind.
Arhanths only have Kiriya Cittas. Those are of 3 types.
i. Consciousness turning to impressions at the five doors
(panca dvara-avajjana) accompanied by feeling of indifference(Upekkhā).
ii. Consciousness turning to impressions at the mind-door
(mana dvara-avajjana) accompanied by feeling of indifference(Upekkhā).
iii. Consciousness of the genesis of smile (hasitoppada
citta) accompanied by joy(Pīti).
Hasita(a smile which slightly reveals the tips of the teeth) is their reaction to joy. If they ever cried, there should be another called the Assuppada citta. But there isn't! :)

533: <p>What is the Buddhist view on crying? I don't remember hearing or reading about the Buddha ever crying. Is crying a consequence of "lack of understanding" of the ultimate reality?</p>
 7611: <p>An enlightened person who has achieved arahantship has put an end to mental fermentations, so how would they cry?</p>

<p>Fermentations which would cause one to cry, experience grief and sorrow wouldn't be there. </p>

<p>This means they could only pretend to cry or have the appearance of crying but not actually experience grief or sorrow.</p>

<blockquote>
  <p>"From craving springs grief, from craving springs fear. For one who is wholly free from craving there is no grief; whence then fear?" (Dhammapada, 216)</p>
</blockquote>

<hr>

<blockquote>
  <p>"Whoever is overcome by this wretched and sticky craving, his sorrows grow like grass after the rains."</p>
  
  <p>"But whoever overcomes this wretched craving, so difficult to
  overcome, from him sorrows fall away like water from a lotus leaf."
  (Dhammapada, 335-336)</p>
</blockquote>

<p>Nibbana is the highest bliss, highest enjoyment, with fermentations (asavas) put to an end how can someone cry, be fearful, sorrowful, angry? Experiencing such an extreme form of enjoyment why would anyone cry?</p>

<p>Doubtless, fearless, sorrowless, angerless, calm, and happy walks the arahant.</p>
 715: <blockquote>
  <p>What is the Buddhist view on crying?</p>
</blockquote>

<p>We must not pretend to be the Buddha, if tears come, we must respect that while investigating causes and conditions, using the moment as a teacher, to gather fresh insight. When true understanding is born, the tears will naturally dry up. New tears of compassion may form as one walks the path of the Bodhisattva.</p>

<p>Bodhisattvas have cried at seeing the fate of those in pain, and enlightened people like Jesus have shed compassionate tears. </p>

<blockquote>
  <p>I don't remember hearing or reading about the Buddha ever crying.</p>
</blockquote>

<p>I can't recall any suttas that talk about the Buddha crying or not, but I am not a Tipitaka master. It is <a href="https://buddhism.stackexchange.com/questions/9824/what-are-the-eighteen-buddha-attributes">not explicitly one of the 18 Buddha attributes</a>. One can surmise therefore that this is not considered a very important distinction.</p>

<p>The key aspect of a Buddha is volition. If he cried at all, it would not be meaningless. </p>

<blockquote>
  <p>Is crying a consequence of "lack of understanding" of the ultimate
  reality?</p>
</blockquote>

<p>Yes and no - Involuntary crying of the nature humans often perform - where we try to hold back our tears, yet the circumstance overpowers us should not be the case for the Buddha. He has no remaining sankharas, no hidden traumas in the mind, no lack of control over his actions and perfect understanding of cause and effect.</p>

<p>If his crying served a purpose, then he may cry because it is <em>Upaya</em>. </p>

<p><strong>Caveat:</strong> <em>I am no Buddha, so I can't know for sure. It makes me a little uncomfortable to deal in the hypothetical.</em></p>
 111: <p>Crying can be caused due to both physical and mental reasons.</p>
<p><strong>Physical reasons:</strong></p>
<ol>
<li>Irritation in the eyes.</li>
<li>Sickness affecting the eyes.</li>
<li>Side effects of strong medication or extremely spicy food.</li>
</ol>
<p><strong>Mental reasons:</strong></p>
<ol>
<li>Sadness(obvious sadness and the sadness disguised as compassion), depression, aversion to pain, fear</li>
<li>Clinging to happy/pleasant/joyful states of the mind.</li>
</ol>
<p>Assuming that this question is aimed at the 2nd category, it is highly unlikely that a fully enlightened being would cry as they no longer become sad or cling to pleasant states of the mind.</p>
<p>Arhanths only have <a href="http://www.wisdomlib.org/definition/kiriya-citta" rel="nofollow noreferrer">Kiriya Cittas</a>. Those are of 3 types.</p>
<p>i. Consciousness turning to impressions at the five doors
(panca dvara-avajjana) accompanied by feeling of indifference(Upekkhā).</p>
<p>ii. Consciousness turning to impressions at the mind-door
(mana dvara-avajjana) accompanied by feeling of indifference(Upekkhā).</p>
<p>iii. Consciousness of the genesis of smile (hasitoppada
citta) accompanied by joy(Pīti).</p>
<p>Hasita(a smile which slightly reveals the tips of the teeth) is their reaction to joy. If they ever cried, there should be another called the Assuppada citta. But there isn't! :)</p>
