Kural - 300

Of all good things we've scanned with studious care,
There's nought that can with truthfulness compare

Explanation
Amidst all that we have seen (described) as real (excellence), there is nothing so good as truthfulness.

Tamil Transliteration
Yaameyyaak Kantavatrul Illai Enaiththondrum
Vaaimaiyin Nalla Pira.