As time passes, with Hashem’s help the beginner learns step by step, albeit on a basic level, what’s what. But his thirst is not satiated with learning the amount that most others suffice with. He continues learning deeper and more advanced teachings, perhaps even surpassing many others in his community.
This is where the pitfall lies. As long as one lives, the Yetzer Hara (evil inclination) is seeking crafty ways to cause confusion, to distract the person and lead him away from serving Hashem. Even as one draws close to Hashem, the Yetzer Hara can use that very act against the person.
One danger of learning and practicing Torah and Yiddishkeit is that the more the person does it, and the more he learns about it, the more he thinks—very subtly, perhaps not even consciously—that now he really knows, and this plants a minute but growing sense of satisfaction, complacency, and arrogance. This is evident in the fact that although he still learns, he no longer does so with the sense of thirst and deprivation felt by a beginner.
But this feeling is unjustified, for in reality he has merely glimpsed an infinitesimal fraction of the vast expanses of Torah, whose “measure is longer than the earth, and wider than the sea” (Job 11:9). He may indeed have made tremendous progress in comparison to his previous level. However, when compared with what Torah truly is, even after decades of intensive learning, he has barely scratched the surface. Similarly, through Torah one connects with Hashem, Who is infinite, and therefore no matter how close one has come to Hashem, he always remains far from Hashem’s infinite reality. As long as the person realizes and senses this, he will always yearn for more.