Bilaam said, "Let me die the death of the upright." Meaning, he aspired to the eternal delight of the World to Come. However, soon after making this declaration, he accepted money to advise Balak on how to damage the Nation of Israel.
The man, who professed a desire for eternal life, made an abrupt about-face and forfeited any hope of receiving a portion in the Next World. How do we understand the personality of such a sudden and extreme shift in goals?
While Bilaam intellectually understood the precious quality of the World to Come, he did not instill this idea deeply in his heart. Since he did not internalize his spiritual goals, he was vulnerable to the bodily forces. Therefore, as soon as he was tempted by the material pleasures of this world (i.e., in this case, money), he dropped his spiritual goals.
A little more contemplation on his part would give him the clarity to set his goal on the higher delights of Gan Eden. He would see that this world is temporal - and laden with much frustration and exertion. Whereas Gan Eden is eternal, its delight and peace are supreme - and unadulterated.
Contemplate on the eternal, supreme pleasure of Gan Eden in contrast to the finite, inferior pleasure of this world.
[Based on Ohr RaShaz of the Alter of Kelm, Rabbi Simcha Zissel]