nce of the Grail itself is not found in the metal of the cup but in the religious power it contains and represents. The attainment of the Grail in Lancelot's case will not be as important as the seeking after it, and the spiritual awakening which he experiences as a result of the suffering and education he acquires during that seeking. This is why the experience is called the Quest for the Grail, rather than the attainment of the Grail. The fact that he does not attain the Grail does not mean that he has not attained the religious experience which the Grail symbolizes.
Of course, it is also crucial that the reader see that one of the reasons--if not the only reason--that Lancelot does not attain the Grail is his own imperfection, his own impurity, which is certainly represented by his adultery with Guinivere. The Grail cannot be won by any individual with impurity, from which Lancelot's son Galahad is free while his father is not. On the other hand, the decision by Lancelot and Guinivere to make their relationship chaste and spiritual is a sign of the impact the search for the Grail has had on him.
In fact, Lancelot is at the center of the Grail story precisely because he is flawed and, therefore, has moral and spiritual room to grow as a result of the quest. had he been utterly pure, the drama of the quest would have been minimized if not eliminated. Most readers would likely id
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