SB 4.29.49

āstīrya darbhaiḥ prāg-agraiḥ
 kārtsnyena kṣiti-maṇḍalam
stabdho bṛhad-vadhān mānī
 karma nāvaiṣi yat param
tat karma hari-toṣaṁ yat
 sā vidyā tan-matir yayā
Synonyms: 
āstīrya — having covered; darbhaiḥ — by kuśa grass; prāk-agraiḥ — with the points facing east; kārtsnyena — altogether; kṣiti-maṇḍalam — the surface of the world; stabdhaḥ — proud upstart; bṛhat — great; vadhāt — by killing; mānī — thinking yourself very important; karma — activity; na avaiṣi — you do not know; yat — which; param — supreme; tat — that; karma — activity; hari-toṣam — satisfying the Supreme Lord; yat — which; — that; vidyā — education; tat — unto the Lord; matiḥ — consciousness; yayā — by which.
Translation: 
My dear King, the entire world is covered with the sharp points of kuśa grass, and on the strength of this you have become proud because you have killed various types of animals in sacrifices. Because of your foolishness, you do not know that devotional service is the only way one can please the Supreme Personality of Godhead. You cannot understand this fact. Your only activities should be those that can please the Personality of Godhead. Our education should be such that we can become elevated to Kṛṣṇa consciousness.
Purport: 

In this verse the great sage Nārada Muni directly insults the King because he was engaged in performing sacrifices that entail the killing of a great number of animals. The King was thinking that he was great for having performed so many sacrifices, but the great sage Nārada directly chastises him, informing him that his animal-killing only leads to his being puffed up with false prestige. Actually, anything that is done which does not lead to Kṛṣṇa consciousness is a sinful activity, and any education that does not lead one to understand Kṛṣṇa is false education. If Kṛṣṇa consciousness is missing, one is simply engaged in false activities and false educational pursuits.