Kural - 676

Accomplishment, the hindrances, large profits won
By effort these compare,- then let the work be done

Explanation
An act is to be performed after considering the exertion required, the obstacles to be encountered, and the great profit to be gained (on its completion).

Tamil Transliteration
Mutivum Itaiyoorum Mutriyaangu Eydhum
Patupayanum Paarththuch Cheyal.