Kural - 178

What saves prosperity from swift decline?
Absence of lust to make another's cherished riches thine

Explanation
If it is weighed, "what is the indestructibility of wealth," it is freedom from covetousness.

Tamil Transliteration
Aqkaamai Selvaththirku Yaadhenin Veqkaamai
Ventum Pirankaip Porul.