Why do they bury the body of the sages? What is JeevaSamadhi? -Thirumoolar

Thirumoolar has told that the body of one without fame has to be burnt , and the body of one with fame has to be buried.

"எண்ணிலா ஞானி உடல் எரிதாவிடில்

ennilaa gnani udal erithaavidil

அண்ணலதம் கோயில் அழலிட்ட தாங்கொக்கும்

annalatham koayil azalitta thaangokkum

மண்ணில மழை விழா: வையகம் பஞ்சமாம்

mannil mazhai vizaa: vaiyagam panjamaam

எண்ணரும் மன்னர் இழப்பார் அரசுமே

ennarum mannar izappaar arasumae"

- திருமந்திரம் (Thirumanthiram)

"அந்தமில் ஞானி அருளை அடைந்தக்கால்

anthamil gnani arulai adainthakkaal

அந்த உடல்தான் குகைசெய்து இருந்திடில்

antha udalthaan kukaiseythu irunthidil

சுந்தர மன்னரும் தொல்புவி உள்ளோரும்

sunthara mannarum tholpuvi ulloarum

அந்தமில் இன்ப அருள்பெறு வாரே

anthamil inba arulperu vaarae"

- திருமந்திரம் (Thirumanthiram)

The sages are those who consider their body as temple. Burning that body is like burning the temple itself. If we do like that that there would be no rains on the earth. The king may tend to loose his kingdom. If there is nobody to bury the body of the sages and if the body is let on the ground it decomposes and the beauty of the world is lost and the kingdom falls off and a great loss occurs says Thirumoolar. 

If their body is buried then for the people of country attains goodness, the country gets a great wealth, the people of the country will be blessed says Thirumoolar. Those who have been buried will once again come  out and roam around and again enter into the sepulcher back. Hence they do not say that they are buried rather they say they are made as Jeeva Samadhi*. 

*Jeeva - Life/soul;  Samadhi - Intense Yogic contemplation of becoming oneness with God.