That Man is the product of causes which had no prevision of the end they were achieving; that his origin, his growth, his hopes and fears, his loves and his beliefs, are but the outcome of accidental collocations of atoms; that no fire, no heroism, no intensity of thought and feeling, can preserve an individual life beyond the grave … Only within the scaffolding of these truths, only on the firm foundation of unyielding despair, can the soul's habitation henceforth be safely built. ~ Bertrand Russel, famous atheist philosopher, Mysticism and Logic (emphasis added)

Hope doveNote that Russel is not arguing that all atheists actually do face the world with despair. He's not saying that all atheists are depressed or something. He's arguing that the logical conclusion of life terminating upon death is to face the world with despair. Of course few, if any, can actually do that, since it's not only psychology impossible to live consistently that way, it's also illogical to build a "firm foundation" upon nothing; "despair" is not a firm foundation, it is a lack of one.

On the other hand, Christians do not face death with despair. Consider Hebrews 11:1: "What is faith? It is the confident assurance that what we hope for is going to happen. It is the evidence of things we cannot yet see." Here faith is evidence for the hope that we can quite rightly have, not despair. Of course, faith is that, and much much more, but that is an important part.

For a more thorough article on this topic, please see Dustin Shramek's article, "Atheism and Death: Why the atheist must face death with despair".