Śrīmad-Bhāgavatam · Text 11.11.18
शब्दब्रह्मणि निष्णातो न निष्णायात् परे यदि ।
श्रमस्तस्य श्रमफलो ह्यधेनुमिव रक्षत: ॥ १८ ॥
śabda-brahmaṇi niṣṇāto
na niṣṇāyāt pare yadi
śramas tasya śrama-phalo
hy adhenum iva rakṣataḥ
If through meticulous study one becomes expert in reading Vedic literature but makes no endeavor to fix one’s mind on the Supreme Personality of Godhead, then one’s endeavor is certainly like that of a man who works very hard to take care of a cow that gives no milk. In other words, the fruit of one’s laborious study of Vedic knowledge will simply be the labor itself. There will be no other tangible result.
Read the purport on Vedabase.ioFrom Canto 10, chapter 14 onward, the translation and purports were completed by Śrīla Prabhupāda's disciples after his departure, and published by the Bhaktivedanta Book Trust.