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Regarding the experience of the arahant, the Suttanipaata states that by the destruction of all feelings/sensations a monk lives desireless and at peace.11 Once Saariputta was asked what happiness there can be when there is no feeling/sensation.12 He explained that the absence of feeling/sensation itself is happiness.13 It is relevant to note here that the Buddha says that he does not speak of happiness only with reference to pleasant feelings/sensations. Wherever there is happiness or pleasure, that he recognizes as happiness or pleasure.14
Here we are reminded of the statement that all mental states converge on feelings.15 What is meant by this statement seems to be that all mental states are translated into sensations in the body. It is possible to understand the import of this statement if we pay attention to a gross emotion, such as anger. When we are angry we experience a variety of bodily sensations: feeling hot, being restless, breaking out in a sweat, trepidation, etc. When we are sad, tears come into our eyes. These are brought about by changes in body chemistry through the discharge of various glandular secretions. If intense emotions bring about such gross sensations, we might conjecture that all thoughts cause subtle sensations in the body resulting from changes in body chemistry. We are hardly aware of these sensations which, however, become noticeable with the development of vedanaanupassanaa, contemplation of sensations. Thoughts are endless and continuous; therefore, if this interpretation that thoughts are translated into sensations is correct, sensations too should be endless and continuous. The Vedanaasa.myutta states that just as diverse winds constantly blow in different directions, numerous sensations pass through the body.16
An arahant has full control over his thoughts;17 therefore he must have full control over his feelings/sensations too. What is meant by the statement that "a monk lives desireless and at peace by the destruction of all feelings/sensations" seems to be that he has destroyed all psychogenic feelings/sensations. This leads us to another statement: that all feelings/sensations partake of the nature of suffering.18 In order to understand the significance of this statement we must pay attention to our postures. If we have to remain seated for some time, say for an hour, we are not even aware of how many times we shift and adjust our limbs to more comfortable positions. This happens almost mechanically, as all the time we unconsciously seek to avoid discomfort. This is because monotony of sensations, even pleasant sensations, brings about discomfort and a change brings about a temporary sensation of comfort. If there were no sensations produced from within perhaps we would not need to change positions so often and we would have a running sense of ease even if we continue to remain in the same position for a long time.
Here it might be asked whether an arahant has lost the ability to feel pain, which is also an essential part of the touch sensation. It has to be pointed out that this is not so, for in that case an arahant would not even know if a part of his body is seriously injured or burnt. There is plenty of evidence to show that an arahant does feel sensations caused by physical changes. For instance, the Buddha felt acute pain when he was wounded by a stone splinter19 and when he suffered from indigestion.20 But he was able to withstand the painful sensations with mindfulness and clear comprehension without being fatigued by them. Again, an experience of Saariputta throws light on the subject.21 His experience refers to events which modern psychology designates as "non-ordinary reality of altered states of consciousness." A yakkha, a malevolent spirit, once gave Saariputta a blow on the head. The blow, it is said, was so powerful that it was capable of splitting a mountain peak or making a seven and a half cubit high elephant go down on its knees. Moggallaana, who saw the incident with his divine eye, inquired from Saariputta how he was feeling. He replied that he was all right, but there was slight pain in the head. This shows us that a blow which could have deprived an ordinary person of life had only minimal impact on an arahant.
Perhaps because the psychological factors which predispose a person to the experience of sensations are perfectly well under control in an arahant, he experiences only those sensations that are felt purely physically by an animate
organism. It seems as if the body is under some sort of mentally regulated anesthesia which allows a narrow margin of sensation to protect the body from external danger. There are two kinds of pain, physical and mental,22 and arahants are said to experience only physical pain,23 without the anxious mental agony when experiencing physical pain.
It is also possible to look at this issue from another angle. Though the texts state that vedanaa is destroyed in the arahant, they never say that the sense faculties are destroyed. When describing the super-conscious state of sa~n~naa-vedayitanirodha, the sense faculties are said to be refined — vippasannaani indriyaani.24 So in the case of the arahant, too, the sense faculties must certainly be refined and not rendered deficient in any way. In that case it is possible to surmise that, though vedanaa is extinct, body-sensitivity continues to be active and is thoroughly refined.
Nibbana as Living Experience / The Buddha and The Arahanthttp://www.accesstoinsight.org/lib/auth ... el407.html
In sitting meditation stay with that ‘which knows’ everything. Don’t try to go to objects. Let the objects come to you. Try not to react to objects. Whatever arises — greed, aversion, pain, itchiness, metta, likes or dislikes etc. — watch with equanimity, without getting involved, without clinging to it. Stay in the middle path.- Shwe Oo Min Sayadaw