If you want him to believe that Lu Ren has only spent a mere hundred years to reach the Earth Immortal realm, the Tathagata would surely chuckle, then twist your head off to see what's inside, for uttering such childish nonsense.
"Guard the Human Race?"
The Tathagata looked slightly stunned and then cursed inwardly that you're willing to initiate a battle for mere mortals, must be overfed, since there's countless scattered throughout the galaxy, why argue here?!
Despite the constant grumblings in his heart, the Tathagata made sure not to show any of it outwardly.
Lu Ren saw the expression on the Tathagata's face and naturally understood what the other was thinking. These folks regard mortals as pigs and dogs, resources that can be used at will, only needing to mind the population numbers remaining not too scarce, with the rest as unrestricted use.
